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So I've been through the wringer with this car now. Idle issues and electronic issue after issue reporting MAF codes, throttle position sensor codes, CAT codes and couple others. Car ran great until it wouldn't idle anymore and now that's all it does is not idle right. Took it to the dealership because one of the shops said that all the issues relate to an update to the PCM for the MAF voltage and it is a dealer only update. Well, they spent 20 minutes and said it wasn't even worth charging to look at it because there is so much wrong with it. Says he can grab the wiring harness and it will change the idle. Says they don't even sell the wiring harness anymore. A to B car for my boy for college. What do I do?
Anyone know where to find a wiring harness? Is that where I start? Is there anyone I could actually TALK to about this to help give me some direction on what/how to get this car running again? Just need some help cause I can't afford to go buy a new car for this kid. This is a desperate attempt at some help...look at my other posts if you want to see what all the idle issues are about. I haven't done all the component testing...I am just a little "hands in the air" with this car right now and simply don't know where to start. I just need to get it running again so he can get to school and take out the girls.
Getting a junkyard to pull a harness or going to a u-pull-it should yield the results you need. Bad idle could be so many things. I've never dealt with it in these cars except the iacv. I swapped mine and it didn't blow the ECU so I got lucky. I would start with the harness and air leaks. Harness is a known issue and air leaks are next to free to fix.
You should probably slow down first. From what I see here, is that when you are getting a lot of fault codes, there is usually a root problem that is at fault. What codes are you seeing? What is the behavior of the engine? How long has this been happening? More details are only going to help.
You may have to go over to Nissan for the Harness connectors, sub-harness connectors,
Heres a link to their tech info on those
www.nissantechmate.com/tools
OP, list the codes you are getting, and indicate whether pending or stored.
You may only have to replace one-two sensors, or it may be more involved, it depends on codes.
You should probably slow down first. From what I see here, is that when you are getting a lot of fault codes, there is usually a root problem that is at fault. What codes are you seeing? What is the behavior of the engine? How long has this been happening? More details are only going to help.
Engine codes P1446PD, P0100, P0120, P0105, P0105PD
Engine behavior has been random version of the following:
Extended crank - this is always producible after the car has sat for a while. If you start it, shut it off, and then restart it, it will sometimes crank long, sometimes not
Intermittent RPM oscillation after start - This may be warm and cold start, but seems most common on cold start. The RPMs will oscillate between 6-700 RPMs until the car gets warm(er)
Herky-Jerky - Only when cold. Any gas pedal release is exaggerated and jerks you everywhere. Any light movement with the gas pedal while engine very cold causes this herky-jerky movement of the vehicle. Doesn't do it at all after warm.
No idle - Just that. It won't idle at all and drives with a big misfire, smells of gas, and smokes. After I dropped the car off at the dealership yesterday , i started it up and it drove home like it had 40k miles on it. They messed with something and all the sudden, boom, it just works fine.
Below is the video - smells like gas when it runs like this and the CAT gets super hot and smokes, assuming this is because it is running too rich.
The gas smell may be dysfunctional injectors
Fuel injectors dont just cut out as you would think they wear and wind up dumping too much fuel
One way to test those for leaking
Pull the upper plenum
YouTube
https://youtube.com/watch?v=SENDHtDeyio
lHold up the rail with injectors cliped in
Turn on the ignition where your dash lights all light up
Then walk out and see if any gas is leaking from the injectors. If so those will need to be replaced with new injectors.
The jerking could be several issues
Clean the MAF real well in the tunnels and all the plates.
Also reset the TPS by twisting it until theres no continuity within the closed position circuit. Pins 4&5 are the two pins to hook the volt meter up
Last edited by maximatech12; 01-31-2018 at 03:48 PM.
Isn't super hot cats because because they are plugged? You could take out an oxygen sensor to test it. If the injectors we're dumping way to much fuel cats can get clogged quickly. But I said start with the harness because you said it worked fine after that got messed with.
Let's start from the beginning: Your car was modified, perhaps extensively. I think I can assume that these mods were done by the previous owner .... and that he did not provide you with the documentation on how/why these mods were done. Correct?
Now, there are three ways to get out of this mess:
A) I suggest contacting the previous owner and obtaining the missing documentation. Once you have it, you should be able to proceed, with focus on the codes (P0100, P0105, P0120). More about that below.
B) If you can't obtain any documentation for the mods made to your car, you can try to fix it "as is", relying on the codes provided. Tricky.
C) Finally, you can try to replace the harness and hope that this will restore the car to its OEM state. Not a pleasant task, with a lot of "hit and miss", and possibly quite expensive. (Besides, how would you know whether/when you are finished??)
In either case, your car's ECU is telling you what it thinks is wrong:
P0100 - your MAF or the associated wiring/connectors.
P0105 - your Absolute Pressure Sensor (MAP) and/or the associated wiring.
P0120 - your Throttle Position Sensor (TPS) and/or the associated wiring.
P1446 - Evap Canister issues; ignore for the time being (emissions-related only).
Re. replacement parts, you can obtain all three sensors for about $250 ($122 + $78 + $52) from Rockauto. All OEM parts, made by Hitachi.
My personal guess is that one/more of these sensors is bad, and/or that one/more of the associated connections (and the "T splits in particular) is/are bad. Good luck, you'll need it.
Can't help it to make one final comment: This is why you NEVER/EVER buy a car that was moddded by an amateur !!!!
Let's start from the beginning: Your car was modified, perhaps extensively. I think I can assume that these mods were done by the previous owner .... and that he did not provide you with the documentation on how/why these mods were done. Correct?
Now, there are three ways to get out of this mess:
A) I suggest contacting the previous owner and obtaining the missing documentation. Once you have it, you should be able to proceed, with focus on the codes (P0100, P0105, P0120). More about that below.
B) If you can't obtain any documentation for the mods made to your car, you can try to fix it "as is", relying on the codes provided. Tricky.
C) Finally, you can try to replace the harness and hope that this will restore the car to its OEM state. Not a pleasant task, with a lot of "hit and miss", and possibly quite expensive. (Besides, how would you know whether/when you are finished??)
In either case, your car's ECU is telling you what it thinks is wrong:
P0100 - your MAF or the associated wiring/connectors.
P0105 - your Absolute Pressure Sensor (MAP) and/or the associated wiring.
P0120 - your Throttle Position Sensor (TPS) and/or the associated wiring.
P1446 - Evap Canister issues; ignore for the time being (emissions-related only).
Re. replacement parts, you can obtain all three sensors for about $250 ($122 + $78 + $52) from Rockauto. All OEM parts, made by Hitachi.
My personal guess is that one/more of these sensors is bad, and/or that one/more of the associated connections (and the "T splits in particular) is/are bad. Good luck, you'll need it.
Can't help it to make one final comment: This is why you NEVER/EVER buy a car that was moddded by an amateur !!!!
So even given the fact that the tech at the dealership says that when he messes with the wiring harness it changes the throttle behavior you would recommend that I replace all these parts? It wasn't "modded" the same as you are thinking. We found out that there is a service bulletin for the voltage on the MAF and that is why there is a wire running from the hot wire on the MAF directly to the hot wire on the PCM - to help correct a voltage problem from the PCM? Am I better off replacing the parts locally and taking them back if they don't fix the issue? I didn't know anything was modded - I am not in the habit of looking at the wiring harness to see if it's had modifications to it. Lesson learned.
If Maxima throttle pedal position sensor is anything like Quests, it's worth starting there. Does your engine ever refuse to rev up when you push the gas pedal?
The maf code can be from a corroded ground in the maf harness. mine got brittle and corroded at the connector and down thw wire
I have been over this MAF connector forwards and backwards. I can tell you that it doesn't "lock" on the actual sensor - the harness for the MAF is broken so it just pushes on and slides off - no thumb action required to remove it.
I agree a new connector! You ever done one? I can not say yes it will solve your issue however ot will give you piece of mind.
Ive seen the pigtail for that online and in store and it looks like 16AWG so youll need some butt splices, a, heat gun, crimping tool, and splicing tool! All can be aquired at Harbor Freight online or auto zone.
So even given the fact that the tech at the dealership says that when he messes with the wiring harness it changes the throttle behavior you would recommend that I replace all these parts?
No, I am not saying that you should change all these parts, at least not right away. The fact that "messing up with the harness" changes the throttle behavior means that there is something wrong with the harness; more likely, with the "T-splits" that somebody added.
Originally Posted by heuster
It wasn't "modded" the same as you are thinking. We found out that there is a service bulletin for the voltage on the MAF and that is why there is a wire running from the hot wire on the MAF directly to the hot wire on the PCM - to help correct a voltage problem from the PCM?
Service bulletin for the MAF voltage?? Never heard of it, and I own a 2000 SE, have bought it new (back in January 2000), and the car runs just fine without any mods to the MAF circuit!! Have you read the service bulletin yourself, or you are just repeating what somebody told you??
Originally Posted by heuster
Am I better off replacing the parts locally and taking them back if they don't fix the issue? I didn't know anything was modded - I am not in the habit of looking at the wiring harness to see if it's had modifications to it. Lesson learned.
You didn't know anything was modded?? Well, what is this "hot wire on the MAF directly to the hot wire on the PCM", and all the stuff (T-splits, etc.) clearly visible on your video???
So, I would recommend that you:
- Get the "service bulletin", read it, and report back to us.
- I feel you'll need to fix your harness issues first (best, return the harness to its original/OEM state) before replacing any parts.
I have been over this MAF connector forwards and backwards. I can tell you that it doesn't "lock" on the actual sensor - the harness for the MAF is broken so it just pushes on and slides off - no thumb action required to remove it.
Well, that's a problem. It needs to "click and lock".
Think about what your saying : "a new harness"
Thats all the wires from the ECM running through the whole motor!
Thats going to cost you over $2000!
You could file a claim with Nissan for them to cover the part or something
Last edited by maximatech12; 02-01-2018 at 08:30 PM.
You don't need a new wiring harness. A complete harness is a lot of money even if you get a used one. I would keep that as a last resort. You can't buy individual harness pieces new or even used unless you go to the You-Pull-It yard and cut them out yourself. Then they're cheap.
I would cut open the harnesses and put them back to stock before swapping any parts. Hopefully you can cut and splice wires pretty well. If you find one in the salvage yard you can cut open the harnesses and see how they're supposed to look.
If Maxima throttle pedal position sensor is anything like Quests, it's worth starting there. Does your engine ever refuse to rev up when you push the gas pedal?
When it is acting up it can do all kinds of weird things. Watch the video I posted and you'll see the acceleration behavior. Very herky-jerky in the cold AM if it's idling fine and it will randomly bog down while driving and run like crap with a misfire etc.
No, I am not saying that you should change all these parts, at least not right away. The fact that "messing up with the harness" changes the throttle behavior means that there is something wrong with the harness; more likely, with the "T-splits" that somebody added.
Service bulletin for the MAF voltage?? Never heard of it, and I own a 2000 SE, have bought it new (back in January 2000), and the car runs just fine without any mods to the MAF circuit!! Have you read the service bulletin yourself, or you are just repeating what somebody told you??
You didn't know anything was modded?? Well, what is this "hot wire on the MAF directly to the hot wire on the PCM", and all the stuff (T-splits, etc.) clearly visible on your video???
So, I would recommend that you:
- Get the "service bulletin", read it, and report back to us.
- I feel you'll need to fix your harness issues first (best, return the harness to its original/OEM state) before replacing any parts.
The info about the service bulletin was told to me by one shop and a another tech down the street that was trying to help me out. I haven't seen it no. I said I didn't know it was "modded" when I bought it - I found all this stuff after the fact. I just wasn't paying attention to the wiring. It's obvious that they removed the air box etc, but I wasn't going through the wiring when I bought it.
It may just be that the red wire into the MAF has a short.
They just ran a t from the end back to where it comes out of the harness loom at the ECU
does the "T" by the floor board go to a red wire that plugs into the computer?
Is the red wire on the edge of the connector?
It should be terminal 111 on the pin diagram.
It may just be that the red wire into the MAF has a short.
They just ran a t from the end back to where it comes out of the harness loom at the ECU
does the "T" by the floor board go to a red wire that plugs into the computer?
Is the red wire on the edge of the connector?
It should be terminal 111 on the pin diagram.
I can give you pictures, but the connection inside the car looks the same as what is on the red wire of the MAF. It is just a clasp on connector and goes from the MAF red wire to the red wire directly out of the computer behind the middle console of the dash in side the car(ECU? PCM?). I can remove that and it doesn't appear to have any major effect, except that the shop pulled it off and regrounded the MAF somewhere else to the frame. The idle behavior started happening a lot more frequently after that and so I hooked up the wire inside the car again and it hasn't helped with anything at all putting it back the way it normally was.
The grounds for the MAF are positioned exactly on the Timing Chain case by the oil fill cap.
Theres two that run to that F39 & F41
Those should be brass terminals and those shouldnt need to be replaced. May just cleaned.
Sounds like you may need to unplug the ECM and run a circuit test between the connector slots on the MAF plug and the corresponding slots within the ECM plug and ground terminals
1 - white wire MAF connect -> 61 white wire ECM connect
2 - red wire MAF connect -> 111 ECM connect
3 - brown wire MAF connect -> 73 ECM connect & grounds on Timing Chain case
4 - red/green MAF connect -> 110&112 ECM connect
Your car should function without the MAF plugged in at all
Maybe another max owner could shed some light on that?
The grounds for the MAF are positioned exactly on the Timing Chain case by the oil fill cap.
Theres two that run to that F39 & F41
Those should be brass terminals and those shouldnt need to be replaced. May just cleaned.
Sounds like you may need to unplug the ECM and run a circuit test between the connector slots on the MAF plug and the corresponding slots within the ECM plug and ground terminals
1 - white wire MAF connect -> 61 white wire ECM connect
2 - red wire MAF connect -> 111 ECM connect
3 - brown wire MAF connect -> 73 ECM connect & grounds on Timing Chain case
4 - red/green MAF connect -> 110&112 ECM connect
Your car should function without the MAF plugged in at all
Maybe another max owner could shed some light on that?
Oh man - your losing me on the circuit test, but as for the MAF unplugged....if I unplug the MAF the car starts right up - no extended crank, no delay, I just can't hit the gas or it sounds like someone put their hand over the mouth of the throttle body.
I had a similar issue with a 2003 Infiniti I35 I bought used for my son. (same engine as the Max). It ended up being the camshaft position sensor. There are two sensors (Bank 1 and Bank 2). Might try replacing both of those and see if that helps. His car was throwing all kinds of codes, idling rough, and even died while driving it in the neighborhood. Once I replaced these two camshaft position sensors, did not have any more issues. They are not expensive, fairly easy to replace, plenty of documentation on how to replace them on youtube.
I had a similar issue with a 2003 Infiniti I35 I bought used for my son. (same engine as the Max). It ended up being the camshaft position sensor. There are two sensors (Bank 1 and Bank 2). Might try replacing both of those and see if that helps. His car was throwing all kinds of codes, idling rough, and even died while driving it in the neighborhood. Once I replaced these two camshaft position sensors, did not have any more issues. They are not expensive, fairly easy to replace, plenty of documentation on how to replace them on youtube.
Are you talking camshaft or crankshaft position sensors? rockauto shows that there is only one camshaft position sensor but there is a front and a rear crankshaft position sensor.
Are you talking camshaft or crankshaft position sensors? rockauto shows that there is only one camshaft position sensor but there is a front and a rear crankshaft position sensor.
You've got two cam sensors. One on each head.
You've got one crank sensor which mounts in the tranny bellhousing towards the front of the car.
I'm not sure what Rockauto is thinking. Different people writing the location of the crank sensor may be making different interpretations of the location. It's towards the FRONT of the car but on the REAR of the motor coming in from the SIDE of the motor.
The front of a motor is where the belts are.
The rear of a motor is where the tranny bolts on.
The right and left side of a motor are as if you were standing behind it like a car.
This works fine in a traditional rear drive setup but with a sideways front drive setup it can cause confusion. That may be what's happening here.
You've got two cam sensors. One on each head.
You've got one crank sensor which mounts in the tranny bellhousing towards the front of the car.
I'm not sure what Rockauto is thinking. Different people writing the location of the crank sensor may be making different interpretations of the location. It's towards the FRONT of the car but on the REAR of the motor coming in from the SIDE of the motor.
The front of a motor is where the belts are.
The rear of a motor is where the tranny bolts on.
The right and left side of a motor are as if you were standing behind it like a car.
This works fine in a traditional rear drive setup but with a sideways front drive setup it can cause confusion. That may be what's happening here.
VQ35DE has 2 cam sensors and 1 crank sensor. I am using a Delphi cam sensor on the front bank for over a year w/o issues. Dunno how to test them in a garage, you probably need a magnet and an oscilloscope.
VQ35DE has 2 cam sensors and 1 crank sensor. I am using a Delphi cam sensor on the front bank for over a year w/o issues. Dunno how to test them in a garage, you probably need a magnet and an oscilloscope.
VQ35DE has 2 cam sensors and 1 crank sensor. I am using a Delphi cam sensor on the front bank for over a year w/o issues. Dunno how to test them in a garage, you probably need a magnet and an oscilloscope.
On this engine there is one camshaft sensor on the front and two crank (POS) and (REF) from every site and video on youtube I could fine for this 3.0. How do I figure this out - does any one have an alldata account they could look?
Are you talking camshaft or crankshaft position sensors? rockauto shows that there is only one camshaft position sensor but there is a front and a rear crankshaft position sensor.
01-30-2018, 01:49 PM
Says he can grab the wiring harness and it will change the idle. Says they don't even sell the wiring harness anymore. A to B car for my boy for college. What do I do?
