Mystery Problem Eludes Mechanics
07-07-2012, 01:51 PM
#1
Thread Starter
Join Date: Jul 2010
Posts: 18
Mystery Problem Eludes Mechanics
Almost no acceleration. (intermittent)
Won't hold idle. (intermittent)
Hiccup at 1700rpm. (always)
Seems cold weather related.
I have a 2000 SE with a 5 speed. In December 2011 the car began to have acceleration problems. The car would only pick up speed under very gentle throttling. Anything more than about 10% on the gas pedal would cause severe hesitation. As if the car were running out of gas. It wouldn't hold an idle without tapping the gas peddle to keep it from stalling. The problem didn't happen all the time but as the winter rolled on I had to stop driving it. It seemed like once the car was warmed up it would start doing this.
I took it to a mechanic who said it was the fuel pump. He wanted $500 to fix it so I did it myself. It didn't change a thing. I then had a friend, who despite his reliability is a pretty smart mechanic, look at it. He checked the fuel pressure which was fine and concluded it was the TPS. So he replaced the sensor and we let it idle for a while. It warmed up and didn't stall. My hopes were high but as soon as I started driving it would stumble/jerk at around 1700rpm in 1st gear and reverse. Not in any other gear or any other range. It didn't get more than a half mile for the acceleration problems and stalling to return.
So the car sat. Waiting for the mechanic friend to return. He never did. So in May (I bought a winter car which has become my summer car) I brought the car to another shop. I towed it there, assuming it wouldn't make it the 3 miles. They were having trouble getting the stalling to occur (not sure about the 1700 rpm hicup). One mechanic took it out at night and stalled on the highway. Had to get it towed. These guys had it for over a month with me checking it on a bi-weekly basis. Eventually they said they couldn't get the car to stall anymore. They didn't have time to deal with it and I had to come pick it up.
I picked it up and rushed it home. Fearing it would stall on me. It didn't. It didn't stall or have any acceleration problems that night or after the 20 or 30 miles I took it around my town today. The hiccup at 1700 RPM in first and reverse are still there.
I'm moving across country in a few months and need to sell the car. I'm afraid this hiccup may be a turn off for a potential buyer. Anyone have any ideas what could be causing the hiccup? What could be causing the idle/stumbling problem? Could it be cold weather related? It started when it got cold became more severe the colder it got, didn't give the second mechanic, who started looking at it in may, any trouble until night time, now that it's warm the stalling problem seems gone. I've replaced the MAF, Crank position sensor, and cam position sensor within the last 2 years.
Won't hold idle. (intermittent)
Hiccup at 1700rpm. (always)
Seems cold weather related.
I have a 2000 SE with a 5 speed. In December 2011 the car began to have acceleration problems. The car would only pick up speed under very gentle throttling. Anything more than about 10% on the gas pedal would cause severe hesitation. As if the car were running out of gas. It wouldn't hold an idle without tapping the gas peddle to keep it from stalling. The problem didn't happen all the time but as the winter rolled on I had to stop driving it. It seemed like once the car was warmed up it would start doing this.
I took it to a mechanic who said it was the fuel pump. He wanted $500 to fix it so I did it myself. It didn't change a thing. I then had a friend, who despite his reliability is a pretty smart mechanic, look at it. He checked the fuel pressure which was fine and concluded it was the TPS. So he replaced the sensor and we let it idle for a while. It warmed up and didn't stall. My hopes were high but as soon as I started driving it would stumble/jerk at around 1700rpm in 1st gear and reverse. Not in any other gear or any other range. It didn't get more than a half mile for the acceleration problems and stalling to return.
So the car sat. Waiting for the mechanic friend to return. He never did. So in May (I bought a winter car which has become my summer car) I brought the car to another shop. I towed it there, assuming it wouldn't make it the 3 miles. They were having trouble getting the stalling to occur (not sure about the 1700 rpm hicup). One mechanic took it out at night and stalled on the highway. Had to get it towed. These guys had it for over a month with me checking it on a bi-weekly basis. Eventually they said they couldn't get the car to stall anymore. They didn't have time to deal with it and I had to come pick it up.
I picked it up and rushed it home. Fearing it would stall on me. It didn't. It didn't stall or have any acceleration problems that night or after the 20 or 30 miles I took it around my town today. The hiccup at 1700 RPM in first and reverse are still there.
I'm moving across country in a few months and need to sell the car. I'm afraid this hiccup may be a turn off for a potential buyer. Anyone have any ideas what could be causing the hiccup? What could be causing the idle/stumbling problem? Could it be cold weather related? It started when it got cold became more severe the colder it got, didn't give the second mechanic, who started looking at it in may, any trouble until night time, now that it's warm the stalling problem seems gone. I've replaced the MAF, Crank position sensor, and cam position sensor within the last 2 years.
Last edited by Ruining My Nissan; 11-07-2012 at 11:14 PM.
07-07-2012, 02:21 PM
#2
Sounds a little bit familiar to me, but not exactly the same. My 02 6-Speed bogs/hesitates under any acceleration except VERY light acceleration. After replacing every part you've listed and then some, I have finally found pretty solid evidence of my problem, which is a clogged pre-cat. When my car is cold, it accelerates just fine, but as soon as it even starts to get warmed up it bogs down. I'm yet to replace it as I'm waiting on a Y-pipe to come in and still have to order a new test pipe/cat and catback exhaust as my exhaust as a whole was all botched together by the previous owner.
I would get a backpressure test or intake manifold vacuum test done to see if you have a clog in your exhaust. The vacuum test is super simple and can be done in a manner of minutes and all you need is a vacuum gauge.
1) Find a vacuum line on your intake manifold
2) Hook up the gauge to that line
3) Start the car
4) Note the initial vacuum reading in mercury
5) Let the car idle for about 10 minutes (or until it reaches normal operating temperature and then a minute or two more)
6) Note the vacuum reading again
RESULTS: If the vacuum reading has increased between ~0.5-1 in/hg then you have a slight clog, if it increases by ~1-1.5 in/hg then you have a significant clog, and if it increases by ~1.5-3 in/hg then your car is trying to sh** through a curly straw. If it does not increase at all or not enough to mention, then your exhaust is flowing fine, and you should look elsewhere.
My car's vacuum increased about 2.2 in/hg indicating a very bad clog in my exhaust system.
You can also read through the thread that I made about my problem, too. You might find something useful in it.
http://forums.maxima.org/5th-generat...l?ref=esp-link
Hope that helps.
-Nathan
I would get a backpressure test or intake manifold vacuum test done to see if you have a clog in your exhaust. The vacuum test is super simple and can be done in a manner of minutes and all you need is a vacuum gauge.
1) Find a vacuum line on your intake manifold
2) Hook up the gauge to that line
3) Start the car
4) Note the initial vacuum reading in mercury
5) Let the car idle for about 10 minutes (or until it reaches normal operating temperature and then a minute or two more)
6) Note the vacuum reading again
RESULTS: If the vacuum reading has increased between ~0.5-1 in/hg then you have a slight clog, if it increases by ~1-1.5 in/hg then you have a significant clog, and if it increases by ~1.5-3 in/hg then your car is trying to sh** through a curly straw. If it does not increase at all or not enough to mention, then your exhaust is flowing fine, and you should look elsewhere.
My car's vacuum increased about 2.2 in/hg indicating a very bad clog in my exhaust system.
You can also read through the thread that I made about my problem, too. You might find something useful in it.
http://forums.maxima.org/5th-generat...l?ref=esp-link
Hope that helps.
-Nathan
07-07-2012, 02:56 PM
#3
Thread Starter
Join Date: Jul 2010
Posts: 18
Nathan,
The bog/hesitation seems related to the cold weather. Now that it's warm it's not showing up at all. So I'm leaning towards the plennum gasket warping in the cold and I see you also replaced that. Is that major surgery? I'm not a mechanic but I'm not an idiot.
If it were a clogged pre-cat, would the symptoms subside in the warmer, more humid, summer air?
Perhaps I'm too focused on this being weather related but what else would account for the problem going away after being very persistent in December and doing nothing more than sitting on my lawn/mechanics parking lot for 6 months?
Currently my only real problem is the glitch/hiccup at 1700rpm in first and reverse.
I do appreciate the response though and will look in the vacuum test.
The bog/hesitation seems related to the cold weather. Now that it's warm it's not showing up at all. So I'm leaning towards the plennum gasket warping in the cold and I see you also replaced that. Is that major surgery? I'm not a mechanic but I'm not an idiot.
If it were a clogged pre-cat, would the symptoms subside in the warmer, more humid, summer air?
Perhaps I'm too focused on this being weather related but what else would account for the problem going away after being very persistent in December and doing nothing more than sitting on my lawn/mechanics parking lot for 6 months?
Currently my only real problem is the glitch/hiccup at 1700rpm in first and reverse.
I do appreciate the response though and will look in the vacuum test.
07-07-2012, 03:30 PM
#4
It's possible that it's related to the cold weather, though it's possible for it to still be a clogged pre-cat even though the symptoms lessen or disappear as the weather changes. It's been ~100*F here in south Louisiana, and it hasn't affected my car at all, but mine has a severe clog, so it may be different if yours has only a minor obstruction.
The plenum gasket was a cake-walk, nothing to it. It's not even entirely necessary to remove the whole manifold, it can be done while it's still bolted up. Not completely certain on whether it's the same on the 3.0, as I never had to change it on my 4th gen, but it should be similar.
Fel-pro actually sells that gasket separately too, and it costs like $3, so don't let anyone tell you that you have to buy the whole gasket set.
One thing though, did you ever do the ECU reset procedure after replacing the parts you did? If all you have left is a hiccup at a specific rpm in just 1st/reverse then it may be as simple as the ECU attempting to compensate for a condition that isn't there anymore. You might try performing the ECU reset procedure and see if that helps clear it up, especially since it doesn't cost you anything except a little time.
Be patient when doing it too, it's a very specific process, and it's easy to stumble when doing it, and then you have to start all over again. Try not to get too frustrated, and just expect to have to try it several times before getting it down pat. I think I had to start over 13 or 14 times before I finally got it to work the first time I tried it. Lol.
-Nathan
The plenum gasket was a cake-walk, nothing to it. It's not even entirely necessary to remove the whole manifold, it can be done while it's still bolted up. Not completely certain on whether it's the same on the 3.0, as I never had to change it on my 4th gen, but it should be similar.
Fel-pro actually sells that gasket separately too, and it costs like $3, so don't let anyone tell you that you have to buy the whole gasket set.
One thing though, did you ever do the ECU reset procedure after replacing the parts you did? If all you have left is a hiccup at a specific rpm in just 1st/reverse then it may be as simple as the ECU attempting to compensate for a condition that isn't there anymore. You might try performing the ECU reset procedure and see if that helps clear it up, especially since it doesn't cost you anything except a little time.
Be patient when doing it too, it's a very specific process, and it's easy to stumble when doing it, and then you have to start all over again. Try not to get too frustrated, and just expect to have to try it several times before getting it down pat. I think I had to start over 13 or 14 times before I finally got it to work the first time I tried it. Lol.
-Nathan
07-07-2012, 03:38 PM
#5
Oh, another question; have you changed/checked your primary o2 sensors? A bad o2 sensor can definitely be a cause for bogging or even hiccuping. My wife's Rav4 needs a new o2 sensor that I've been too lazy to change and she just brought it to my attention that it does the same thing, but at about 2200 rpms. Might be worth checking. The Rav4 has had a bad o2 for over a year now too, and it only just recently set off the service engine light.
Might be worth checking.
-Nathan
Might be worth checking.
-Nathan
07-07-2012, 04:05 PM
#6
Thread Starter
Join Date: Jul 2010
Posts: 18
As for the ecu reset, I did this, but I wasn't sure if I did it correctly. I will look up the procedure and try again. How do you know if you've performed it correctly?
As for the O2 sensor, it's worth a shot. Though the hiccup problem did show up immediately after the TPS was replaced but the stalling problem persisted until some time between May and June while sitting in the mechanics parking lot. So it didn't seem like the TPS fixed the stalling but did start hiccuping. But you may be on to something with the ECU reset.
The brakes are dragging after sitting for 6 months. So I have some work to do.
THANKS.
As for the O2 sensor, it's worth a shot. Though the hiccup problem did show up immediately after the TPS was replaced but the stalling problem persisted until some time between May and June while sitting in the mechanics parking lot. So it didn't seem like the TPS fixed the stalling but did start hiccuping. But you may be on to something with the ECU reset.
The brakes are dragging after sitting for 6 months. So I have some work to do.
THANKS.
07-07-2012, 04:21 PM
#7
No worries. On your 2000, the ECU reset can be performed with a battery disconnect procedure actually. Remove the battery terminals, and hold the positive and negative terminals together for at least 10 seconds. Don't worry, this will not cause damage to your electrical system, all you're doing is completing a circuit. The entire electrical system, including the ECU will be reset and ready to go from square one.
-Nathan
-Nathan
07-08-2012, 09:13 PM
#9
Thread Starter
Join Date: Jul 2010
Posts: 18
Yeah, sorry for the length. I tried to highlight the important sections. It's just stumped a lot of mechanics so I'm trying to be thorough.
I tried the ECU reset. Didn't seem to do anything.
I cleaned the MAF just to see if maybe something had happened to it when we were replacing the TPS. (The bottle of cleaner was cheaper than the sensor, thought it was worth a shot). Didn't make any difference but I'm considering ordering a one.
Still haven't encountered the stalling problem.
When the car is still cold before the idle has settled down, the hiccup doesn't happen. It's after 30-60 seconds of driving, when the temp gauge is at normal operating reading, that's when the problem starts. So what system/sensor doesn't start operating until the car has warmed up? I might buy a new TPS or try testing the wires to the ECU. Does anyone know where I can find good info on the ECU wiring?
I tried the ECU reset. Didn't seem to do anything.
I cleaned the MAF just to see if maybe something had happened to it when we were replacing the TPS. (The bottle of cleaner was cheaper than the sensor, thought it was worth a shot). Didn't make any difference but I'm considering ordering a one.
Still haven't encountered the stalling problem.
When the car is still cold before the idle has settled down, the hiccup doesn't happen. It's after 30-60 seconds of driving, when the temp gauge is at normal operating reading, that's when the problem starts. So what system/sensor doesn't start operating until the car has warmed up? I might buy a new TPS or try testing the wires to the ECU. Does anyone know where I can find good info on the ECU wiring?
07-08-2012, 09:21 PM
#10
Thread Starter
Join Date: Jul 2010
Posts: 18
and by hiccup, it's more like a threshold that the car is reaching where it needs more gas. If I try to hold it steady in range that it's stuck in, the car revs and bucks between about 1500-1800 rpm. If I give it the extra gas to get out of that range the car surges forward. The tires will squeal as now I'm giving it a healthy amount of throttle in first gear at around 2000rpm and we all know how the max reacts to that.
07-08-2012, 10:02 PM
#11
Shot in the dark, but it could be a Coolant Temperature Sensor. They can cause some wacky problems sometimes. Easy piece to test too since it's kind of out in the open, and it's pretty cheap to replace. Mine was $22.
It does sound a lot like a TPS though to be honest, have you tested it since it's been replaced?
And is the new MAFS that you installed an OEM Nissan or an Aftermarket (AutoZone, PepBoys, etc.)?
-Nathan
It does sound a lot like a TPS though to be honest, have you tested it since it's been replaced?
And is the new MAFS that you installed an OEM Nissan or an Aftermarket (AutoZone, PepBoys, etc.)?
-Nathan
07-09-2012, 06:59 AM
#12
Did you or did you not replace it? And if so, did you replace with OEM?
This sounds like a MAFS issue.
07-09-2012, 07:46 AM
#14
Replace the MAFS.
Don't bother doing anything else. Search on here a few guys have found factory replacements for cheap (ish)\\
You will want to buy a thermistor separate at radioshack or whatever and then buy a 2000/2001 MAFS, they're much cheaper, then you just install the thermistor and you're good to go.
Do a little searching on it, there was a recent thread might even be on 1st or 2nd page as well.
Don't bother doing anything else. Search on here a few guys have found factory replacements for cheap (ish)\\
You will want to buy a thermistor separate at radioshack or whatever and then buy a 2000/2001 MAFS, they're much cheaper, then you just install the thermistor and you're good to go.
Do a little searching on it, there was a recent thread might even be on 1st or 2nd page as well.
07-09-2012, 07:28 PM
#15
Thread Starter
Join Date: Jul 2010
Posts: 18
The TPS checked out fine.
I'll look into the MAFS. I couldn't find those threads. Is there any way to test the MAFS? Can I drive the car with the MAFS unplugged?
It seems odd that the bucking problem didn't start until we switched the TPS.
Could the crank position sensor have anything to do with it?
I'll look into the MAFS. I couldn't find those threads. Is there any way to test the MAFS? Can I drive the car with the MAFS unplugged?
It seems odd that the bucking problem didn't start until we switched the TPS.
Could the crank position sensor have anything to do with it?
07-09-2012, 07:57 PM
#16
what do your spark plugs look like and alot of the diesels i work on the egr gets super dirty and tends to stick open when warmed up. it acts like its not getting enough fuel and that would cause alot of the problems your having. if thats the case than it might foul the spark plugs with soot and that would cause your other issues. check your plugs and let us know. its amazing how much those tell us. dont worry about the long posts your doing a great job answering and desribing whats going on. but if you could post a pic of your plugs up close that would be outstanding
07-09-2012, 08:06 PM
#17
you can check the maf by the voltage reading. it should be between .5 and 4.5v depending on the load and engine rpm. youll have a very hard time driving without your maf unless you have a map which i dont know if your car would have one. when my maf didnt work in my 95 5speed i had to floor it to get it moving in first and it wouldnt stay running in any other gear. as far as it starting after you changed the tps its might just be unrelated. but you did say you cleaned the maf and those things are super sensitive and break very easy. cleaning it with a spray can might have cracked it and it could be causing some of your problems
07-09-2012, 10:21 PM
#18
The TPS checked out fine.
I'll look into the MAFS. I couldn't find those threads. Is there any way to test the MAFS? Can I drive the car with the MAFS unplugged?
It seems odd that the bucking problem didn't start until we switched the TPS.
Could the crank position sensor have anything to do with it?
I'll look into the MAFS. I couldn't find those threads. Is there any way to test the MAFS? Can I drive the car with the MAFS unplugged?
It seems odd that the bucking problem didn't start until we switched the TPS.
Could the crank position sensor have anything to do with it?
No where do you say that this issue started with a TPS, you said you did the TPS to fix this issue and it didn't do anything.
In either regard, based on what I see this is what you need to do:
Program the TPS. Anytime you remove or replace this it must be recalibrated. If the calibration is off (likely is) you will get all kinds of nasty stuff going on with idle, engine controls, etc. The throttle is the primary controller in the engine system. If it's wrong it will cause issues.
Becuase it's free, calibrate the TPS first. Use the FSM procedure.
http://www.nicoclub.com/fsm
And if that doesn't fix it >>>> Replace MAFS as suggested earlier. Replace with OEM.<<<<
The cold/warm condition is not helpful in diagnosis unfortuantely when it comes to sensors.
I'll do my best to pass along my understanding, I might be off-base a bit but trying to keep it as simple as possible:
Most sensors don't do anything when the engine is cold. The engine runs in a warm up mode/open loop, focussing almost all it's attention on getting things up to temperature before it starts to read and change imputs for ideal operation. It does this primarily by running a simple 'safe' MAP. Imputs are monitored but don't really effect what happens until the CTS (coolant temp sensor) reads operating temperature.
Then the sensor imputs come into play and engine runs in closed loop, using the sensor imputs to fine tune and control the engine's timing, fuel, throttle position, etc.
CLIFFS: When the engine is cold your sensors don't really effect engine operation
When the engine is at operating temp your sensors have a LARGE effect on engine operation.
07-10-2012, 09:18 AM
#20
Thread Starter
Join Date: Jul 2010
Posts: 18
Tuner,
I'm not looking to argue as you are helping me and I greatly appreciate it but it was mentioned in the OP.
I can't fault you for missing it, it's a lot of details for a post.
The TPS checked out fine. I tested it last night and I get a smooth range from .5 to 4 ohms. So I don't think it's the TPS. At least not the sensor itself, it could be the wiring harness that goes to the computer.
That's useful about the sensors. This explains why the problem doesn't show up until the car is warm. Is there anyway I can rig the CTS to always tell the car it's cold?
Kuhn,
Spark plugs seem fine. The car runs so well when the problem isn't occurring that the mechanics ruled this out.
The cleaning of the MAF took place on Sunday, the problem started in December.
I'm not looking to argue as you are helping me and I greatly appreciate it but it was mentioned in the OP.
So he replaced the sensor and we let it idle for a while. It warmed up and didn't stall. My hopes were high but as soon as I started driving it would stumble/jerk at around 1700rpm in 1st gear and reverse. Not in any other gear or any other range. It didn't get more than a half mile for the acceleration problems and stalling to return.
The TPS checked out fine. I tested it last night and I get a smooth range from .5 to 4 ohms. So I don't think it's the TPS. At least not the sensor itself, it could be the wiring harness that goes to the computer.
That's useful about the sensors. This explains why the problem doesn't show up until the car is warm. Is there anyway I can rig the CTS to always tell the car it's cold?
Kuhn,
Spark plugs seem fine. The car runs so well when the problem isn't occurring that the mechanics ruled this out.
The cleaning of the MAF took place on Sunday, the problem started in December.
07-10-2012, 09:52 AM
#22
I think you have some sort of ground problem.
Has your tranny ever been separated from the motor, like clutch replacement?
Apparently Maximas have this thing where you have to rub the mating surfaces of the tranny and motor down before putting things back together to get a good ground connection between them.
To get around that, you can add a ground between the tranny and motor. Buy a battery cable a screw one side to some point on the motor like the block, the other side to some point on the tranny. Use any existing screws if needed.
If the problem goes away, that's it.
DW
Has your tranny ever been separated from the motor, like clutch replacement?
Apparently Maximas have this thing where you have to rub the mating surfaces of the tranny and motor down before putting things back together to get a good ground connection between them.
To get around that, you can add a ground between the tranny and motor. Buy a battery cable a screw one side to some point on the motor like the block, the other side to some point on the tranny. Use any existing screws if needed.
If the problem goes away, that's it.
DW
07-10-2012, 10:20 AM
#23
Senior Member
Join Date: May 2012
Location: vancouver
Posts: 336
i have a simular issue.
cold- not engaged into gear, if i press the acceration to reach 2000 rpm it will bog at 1700 and drop down and bounce between 1500-1600 rpm. although i can give it a bit more gas and it pushes through the struggle. i only notice this if im gentle with the throttle, if i mash on it it just feels like a miss.
in gear when cold- it will feel kinda bogish/ light misses between 1500 1900 rpm. i notice it more in reverse and 1st right befor it shifts, but still there just super faint in higher gears.
its still there when warm but very very faint
when warm and not in gear with my hand on the motor and puahing the throttle, there is a hiccup when the rpms are coming down at 1700rpm ( i dont really notice anything when giving it throttle in neutral.
when warm in gear- accelerating there is a hiccup at 1700 rpm
when warm and cruising at that specific rpm- it will ever so gently hiccup .
i have checked for- vaccuum leaks, fuel pressure spiking/dropping. i have cleaned TB and IACV, CPS POS and REF (staring issue) replaced TPS and recaliberated, MAF, PCV, pump and strainer, plugs, FPR,TCM,CTS.. and plenum gasket..
I know i have forgotten some other things, i have read that the EGR operations work mostly in that rpm range, could be related to that. i also read someone saying something about the function of the IACV playing a part in this issue.. i will let u know if i come across a solution. please post back if u resolve the issue! good luck.
cold- not engaged into gear, if i press the acceration to reach 2000 rpm it will bog at 1700 and drop down and bounce between 1500-1600 rpm. although i can give it a bit more gas and it pushes through the struggle. i only notice this if im gentle with the throttle, if i mash on it it just feels like a miss.
in gear when cold- it will feel kinda bogish/ light misses between 1500 1900 rpm. i notice it more in reverse and 1st right befor it shifts, but still there just super faint in higher gears.
its still there when warm but very very faint
when warm and not in gear with my hand on the motor and puahing the throttle, there is a hiccup when the rpms are coming down at 1700rpm ( i dont really notice anything when giving it throttle in neutral.
when warm in gear- accelerating there is a hiccup at 1700 rpm
when warm and cruising at that specific rpm- it will ever so gently hiccup .
i have checked for- vaccuum leaks, fuel pressure spiking/dropping. i have cleaned TB and IACV, CPS POS and REF (staring issue) replaced TPS and recaliberated, MAF, PCV, pump and strainer, plugs, FPR,TCM,CTS.. and plenum gasket..
I know i have forgotten some other things, i have read that the EGR operations work mostly in that rpm range, could be related to that. i also read someone saying something about the function of the IACV playing a part in this issue.. i will let u know if i come across a solution. please post back if u resolve the issue! good luck.
07-10-2012, 11:17 AM
#24
1. Have issue
2. Mechanic/friend thinks it's the TPS
3. Replace TPS
4. Still have issue
Unless you're trying to say that a DIFFERENT problem came up AFTER you replaced the TPS. Is that what you're suggesting?
The TPS motor and sensor are adjustable, everytime you remove anything it needs to do a RE-LEARN/CALIBRATE to set up the sensor in referance to the motor position.
To complicate this, the manual procedure (not taking it to the dealer) doesn't always work, and you will get no verification if it DID work. This leaves you with crappy diagnosis.
For this reason, I would suggest you take it to the dealer and just get it done, you'll know 100% that it's complete that way.
If the sensor/motor don't have an accurate reference for where each other are, they're going to do different things. You can imagine how this will cause anything from a small to major issue.
You HAVE TO CALIBRATE THAT SENSOR.
I'll say it once more, put a MAFS in.
If you don't want to buy a good MAFS without knowing for sure, find someone local that has a good running engine and swap the MAFS for his. Clear engine codes and then check it. If the issue is resolved then you know for sure.
That's really the only accurate (ish) way to check your MAFS.
Junkyard MAFS are a complete roll of the dice, you'll need at least 3 to get the odds good enough, and even then who knows? MAFS are super common failure on this car.
Last edited by TunerMaxima3000; 07-10-2012 at 11:19 AM.
07-10-2012, 11:22 AM
#25
Also I'd like to point out:
It's VERY common on here for guys who JUST replaced the MAFS to still have a bad MAFS!!!!!
The cheap MAFS just don't seem to work on this car. You will have problems or they'll only last a short period of time. BUY A GOOD MAFS. If you are having issues after replacing a suspected MAFS and you DIDN"T get an OEM one, then your diagnosis procedure/repair is shot in the foot. You THINK the MAFS has to be good (new, right?) but it could very well be just as bad or worse than the old one.
POST #23 in this thread is a perfect example of a potential cheap MAFS replacement.
It's VERY common on here for guys who JUST replaced the MAFS to still have a bad MAFS!!!!!
The cheap MAFS just don't seem to work on this car. You will have problems or they'll only last a short period of time. BUY A GOOD MAFS. If you are having issues after replacing a suspected MAFS and you DIDN"T get an OEM one, then your diagnosis procedure/repair is shot in the foot. You THINK the MAFS has to be good (new, right?) but it could very well be just as bad or worse than the old one.
POST #23 in this thread is a perfect example of a potential cheap MAFS replacement.
07-10-2012, 11:42 AM
#26
Senior Member
Join Date: May 2012
Location: vancouver
Posts: 336
lol, im post 23..... when did i ever say i put a cheap MAF IN?? I have put.5 different mafs in my car... where would u get the idea of me using a cheap maf???????? i have used refurbished, used and currently have a 500 dillar brand new maf in my car.. didnt change a thing..
Also I'd like to point out:
It's VERY common on here for guys who JUST replaced the MAFS to still have a bad MAFS!!!!!
The cheap MAFS just don't seem to work on this car. You will have problems or they'll only last a short period of time. BUY A GOOD MAFS. If you are having issues after replacing a suspected MAFS and you DIDN"T get an OEM one, then your diagnosis procedure/repair is shot in the foot. You THINK the MAFS has to be good (new, right?) but it could very well be just as bad or worse than the old one.
POST #23 in this thread is a perfect example of a potential cheap MAFS replacement.
It's VERY common on here for guys who JUST replaced the MAFS to still have a bad MAFS!!!!!
The cheap MAFS just don't seem to work on this car. You will have problems or they'll only last a short period of time. BUY A GOOD MAFS. If you are having issues after replacing a suspected MAFS and you DIDN"T get an OEM one, then your diagnosis procedure/repair is shot in the foot. You THINK the MAFS has to be good (new, right?) but it could very well be just as bad or worse than the old one.
POST #23 in this thread is a perfect example of a potential cheap MAFS replacement.
07-10-2012, 12:04 PM
#27
Thread Starter
Join Date: Jul 2010
Posts: 18
Tuner:
Yes, this is the case.
Had stall problem
Replaced TPS
Then had hiccup problem AND stall problem
Car sat for 6 months now just have hiccup problem
So the hiccup and stall seem to be unrelated.
I just put out a facebook post, maybe one of my friends owns a maxima or something.
About the TPS-
You are saying that there is more than just having the sensor seated and getting the correct resistance values? I thought the two were the same, i.e. if it's giving the correct resistance it must be seated correctly.
But I'll try the MAFS before I take it to the dealership.
dwapenyi-
Interesting about the ground. The clutch was replaced about a year and a half before the problem started. What's odd is, a few days prior to any of this happening the clutch fluid was low. I promptly topped it off and assumed the problems were completely unrelated.
user name001-
A quick look around and it doesn't seem to be an uncommon glitch of the maxima. I've come across a few posts that don't ever seem to get resolved.
Yes, this is the case.
Had stall problem
Replaced TPS
Then had hiccup problem AND stall problem
Car sat for 6 months now just have hiccup problem
So the hiccup and stall seem to be unrelated.
I just put out a facebook post, maybe one of my friends owns a maxima or something.
About the TPS-
You are saying that there is more than just having the sensor seated and getting the correct resistance values? I thought the two were the same, i.e. if it's giving the correct resistance it must be seated correctly.
But I'll try the MAFS before I take it to the dealership.
dwapenyi-
Interesting about the ground. The clutch was replaced about a year and a half before the problem started. What's odd is, a few days prior to any of this happening the clutch fluid was low. I promptly topped it off and assumed the problems were completely unrelated.
user name001-
A quick look around and it doesn't seem to be an uncommon glitch of the maxima. I've come across a few posts that don't ever seem to get resolved.
07-10-2012, 12:21 PM
#28
Senior Member
Join Date: May 2012
Location: vancouver
Posts: 336
it definatley isnt an uncommon problem (which is why i have gone through 5 different mafs)
i was just curious on why he was refferring to post #23 which was my post as a potential cheap MAF thats all.
i have my tps set to .60v . i noticed when it was set lower, i had aweful shifts, very sloppy because the trans wasnt timed with the motor properly, mine is also an auto though.. the higher i had it set thw firmer the shifts were.
i read somewhere that the TPS in some cases wasnt even set correctly from factory (read this in another post so dont quote me) i think if iirc, the fsm states anywhere from .28v to .80v is where it should be.
imo, .48- .65 ish seems to be the sweet spot for my auto.
go through the FSM and properly caliberate it.
im not too sure if its only me, but i get a blank page trying to open up the fsm that tuner has posted. i cant back up the correct voltage readings from the FSM cuz i cant open it. but like i said. .60 v with key on engine off is the sweet spot for my auto.
good luck
i was just curious on why he was refferring to post #23 which was my post as a potential cheap MAF thats all.
i have my tps set to .60v . i noticed when it was set lower, i had aweful shifts, very sloppy because the trans wasnt timed with the motor properly, mine is also an auto though.. the higher i had it set thw firmer the shifts were.
i read somewhere that the TPS in some cases wasnt even set correctly from factory (read this in another post so dont quote me) i think if iirc, the fsm states anywhere from .28v to .80v is where it should be.
imo, .48- .65 ish seems to be the sweet spot for my auto.
go through the FSM and properly caliberate it.
im not too sure if its only me, but i get a blank page trying to open up the fsm that tuner has posted. i cant back up the correct voltage readings from the FSM cuz i cant open it. but like i said. .60 v with key on engine off is the sweet spot for my auto.
good luck
07-10-2012, 12:27 PM
#29
the hiccup issue sounds like a MAFS, but if it started when the TPS was replaced, it's more likely an issue with calibration/TPS relearn.
About the TPS-
You are saying that there is more than just having the sensor seated and getting the correct resistance values? I thought the two were the same, i.e. if it's giving the correct resistance it must be seated correctly.
But I'll try the MAFS before I take it to the dealership.
You are saying that there is more than just having the sensor seated and getting the correct resistance values? I thought the two were the same, i.e. if it's giving the correct resistance it must be seated correctly.
But I'll try the MAFS before I take it to the dealership.
I recommend trying the manual procedure in the FSM first. Do it a few times. If nothing changes you might want to just take it ot the dealer to rule it out and ensure it's done.
IF it DOES change then you know that calibration of the TPS was the issue. And you're all set hopefully. This process is tricky and there's some threads out on it, read the FSM procedure, read the DIY/HOWTO threads here first a couple times before even attempting.
If necessary, You should only be charged for 1 hour at the dealer (around $100) to do this programming.
07-10-2012, 05:27 PM
#30
After replacing the original MAF you are supposed to go to Nissan for an ECU update because they change the MAf manufacturer and design, the ECU does not know how to read the info it is being sent. Thia is for 00-01's only
07-10-2012, 09:53 PM
#31
Senior Member
Join Date: May 2012
Location: vancouver
Posts: 336
some say you have to, some say you dont. some say disconnecting the battery for a few hours or loosen both the POS terminal and NEG and hold them together for 10 seconds makes the ECU relearn everything. i had gone through a few mafs, the last one being a OEM, and when they went to update it they said it already had the latest update so i didnt need to. i doubt u really do, some say they noticed more of a difference after the update, and some dont.
personally i dont think you di, but i would disconnect the batt and pump the brakes a few times and leave it for an hour IMO.
personally i dont think you di, but i would disconnect the batt and pump the brakes a few times and leave it for an hour IMO.
07-10-2012, 10:09 PM
#32
Thread Starter
Join Date: Jul 2010
Posts: 18
Tuner-
Is the TPS calibration the same as an idle relearn? I didn't see anything about calibration, just about what specs it should be reading with the multimeter. Is it the same as the ECU reset? Sorry, I searched "calibrate" and "calibration" in the EC.pdf and didn't find anything related to the TPS.
As far as the MAF relearn, I read you didn't have to do it. I think that's what the manufacturer said. At the time, the car went from running like crap to running awesome so I didn't bother. This was about 2 years ago.
Is the TPS calibration the same as an idle relearn? I didn't see anything about calibration, just about what specs it should be reading with the multimeter. Is it the same as the ECU reset? Sorry, I searched "calibrate" and "calibration" in the EC.pdf and didn't find anything related to the TPS.
As far as the MAF relearn, I read you didn't have to do it. I think that's what the manufacturer said. At the time, the car went from running like crap to running awesome so I didn't bother. This was about 2 years ago.
07-11-2012, 09:20 AM
#33
Tuner-
Is the TPS calibration the same as an idle relearn? I didn't see anything about calibration, just about what specs it should be reading with the multimeter. Is it the same as the ECU reset? Sorry, I searched "calibrate" and "calibration" in the EC.pdf and didn't find anything related to the TPS.
As far as the MAF relearn, I read you didn't have to do it. I think that's what the manufacturer said. At the time, the car went from running like crap to running awesome so I didn't bother. This was about 2 years ago.
Is the TPS calibration the same as an idle relearn? I didn't see anything about calibration, just about what specs it should be reading with the multimeter. Is it the same as the ECU reset? Sorry, I searched "calibrate" and "calibration" in the EC.pdf and didn't find anything related to the TPS.
As far as the MAF relearn, I read you didn't have to do it. I think that's what the manufacturer said. At the time, the car went from running like crap to running awesome so I didn't bother. This was about 2 years ago.
Here, I uploaded the pertinent steps/tests you need:
http://s468.photobucket.com/albums/r...ures/01%20TPS/
A couple for here:
07-11-2012, 09:25 AM
#34
As far as the MAFS, I have no idea about it's needing to be calibrated on the 2000/2001. Knight's post is NOT the first time I've heard this though, so you CANNOT rule this out as a potential problem.
I still think this is probably a MAFS issue, but might as well get that TPS set up and checked first, and perform the idle relearn.
The TPS setting you can do yourself, same with testing. Just be accurate.
The Idle relearn is the portion that is hit/miss doing manually. It's a bitter PITA and you have no confirmation of it working.
Idle relearn shouldn't cause this issue IMO, but I don't know that mucha bout it.
I still think this is probably a MAFS issue, but might as well get that TPS set up and checked first, and perform the idle relearn.
The TPS setting you can do yourself, same with testing. Just be accurate.
The Idle relearn is the portion that is hit/miss doing manually. It's a bitter PITA and you have no confirmation of it working.
Idle relearn shouldn't cause this issue IMO, but I don't know that mucha bout it.
07-11-2012, 11:48 AM
#35
Senior Member
Join Date: May 2012
Location: vancouver
Posts: 336
MAFS need to be caliberated to learn the new fuel/air mapping, which driving your vehicle will do after a few 100kms. so either get it caliberated or drive it for a bit and it will do it on its own.
caliberate the TPS by warming your vehicle up, turn it off, key on with engine off, get a multi meter, back off the lower screw on the TPS a tiny bit, loosen the top screw completley. probe the blue wire on top harness, black wire to the NEG battery terminal, slowly move the tps till you read approx. .60v, tighten the phillips screws and recheck to make sure didnt move. start your car, it may or may not idle high (1100 rpm) if it does, do the relearn. done.
caliberate the TPS by warming your vehicle up, turn it off, key on with engine off, get a multi meter, back off the lower screw on the TPS a tiny bit, loosen the top screw completley. probe the blue wire on top harness, black wire to the NEG battery terminal, slowly move the tps till you read approx. .60v, tighten the phillips screws and recheck to make sure didnt move. start your car, it may or may not idle high (1100 rpm) if it does, do the relearn. done.
07-11-2012, 02:37 PM
#36
MAFS are calibrated for the size of housing/tubing they're installed in. A replacement MAFS for the maxima will come pre-calibrated.
You cannot calibrate a MAFS. You can only calibrate the ECM reading it's signal.
Perhaps that's what you were trying to say...
07-11-2012, 08:22 PM
#37
Senior Member
Join Date: May 2012
Location: vancouver
Posts: 336
sorry, yes that is what i was getting at.
ORLY?
MAFS are calibrated for the size of housing/tubing they're installed in. A replacement MAFS for the maxima will come pre-calibrated.
You cannot calibrate a MAFS. You can only calibrate the ECM reading it's signal.
Perhaps that's what you were trying to say...
MAFS are calibrated for the size of housing/tubing they're installed in. A replacement MAFS for the maxima will come pre-calibrated.
You cannot calibrate a MAFS. You can only calibrate the ECM reading it's signal.
Perhaps that's what you were trying to say...
