dfj240

iTrader: (1)

Mine was wrapped in tape as well, I unwrapped it before taking the picture so that it was a little clearer where it was exactly. My new condenser will be here tomorrow, and it cost me $16, including $10 for overnight shipping. So if you can wait a couple days for it, then it should cost less than $10. I have wholesale through both of my local dealers, so with my discount it was going to be $6.33 or something like that.

Or you can order it from courtesy for even cheaper than I can get it. It's $5.88 from them.

http://www.courtesyparts.com/28351m-...3-p-47127.html

That's the link from Courtesy.

-Nathan

RR5

iTrader: (6)

I'd go to a dealer who offers a *cough* discount on parts, but I'm doing a valve body swap. Tomorrow I'll go, before wrapping up today I'll pull the coil condenser out and test it.

7speed

I may leave the front precat with Jeff or catch up with you 2mor when you come in town. I may be out of town Fri.

dfj240

iTrader: (1)

Honestly, Courtesy usually has a better price than you could get from a local dealer even when using wholesale pricing. I just don't like waiting for parts to come in if I can help it, so it's worth the extra money to me to go ahead and get it.

-Nathan

No problem mate. I'll call you or text you when I'm heading towards Dallas, and see if you're available. If not, I'm planning on meeting up with Jeff tomorrow night, so I can get it from him. Thanks again mate.

-Nathan

Amave

man how are you not pulling your hair out of your head by now?

this would be enough to drive me to set my Maxima on fire



i truly hope you get the issue fixed , and if the condensor is the culprit, then take the old one and pulverize it

dfj240

iTrader: (1)

Haha.. I've been pulling my hair out of my head for a week now mate, and I've already got the fuel soaked rag stuck into the fuel tank ready to light.. Hmmm... Maybe that's why it won't run right. Lol.

In all seriousness, I would imagine that if the condenser is indeed the issue, then it could, for all intents and purposes, be the actual cause of coil failure rather than the coils themselves, as they are more likely to overload the coil transistor due to insulation failure than they are to just have no voltage at all.

And thanks again for all the extra brain power to help me think through this and make sure I'm covering everything.

-Nathan

RR5

iTrader: (6)

Only thing I can think of and I got this by watching those Eric The Car Guy videos on youtube (about the misfire on the chevy truck) is to probe the ignition coils and injectors and scope them both.

Perhaps you'll be lucky enough to see ONE acting up and standing out from the others. I think the FSM has a procedure for the ignition coils. EC-717, step 18.

dfj240

iTrader: (1)

Yea, did that before. That's how I found out that ALL of my coils were bad. 2 were replaced by the previous owner, and all four of the others tested bad. So I changed them all out for factory replacements. Talk about expensive too mate. Yikes! Lol.

However, with you bringing that up, it does make me want to go test all of them again to see if they are all still good because of that condenser being bad. So, yea, thanks for bringing that to my attention, I'm going to retest them all tomorrow and see if a bad condenser could cause any of the coils to go bad even in this short of a time period. I'll start with the two that the P.O. replaced and then go from there. Thanks once again mate.

-Nathan

RR5

iTrader: (6)

Should be interesting to see the results. Now I admit I'm worried about the state of my ignition coils but first I've got to rip out the coil condenser to test.

This is exactly why I am over DaveB being let go from SouthPoint Nissan. One call, a short conversation, a parts order and you'd be done.

And you are most welcome. However, one thing comes to mind. If you are going to re-test the igntion coils..you'll have to pull off the intake manifold collector and that means (going by the book) you'll have to replace those gaskets.

knight_yyz

iTrader: (40)

knock sensor

dfj240

iTrader: (1)

Indeed you are correct RR5. And to be honest, I am a "by the book" kind of mechanic. It's more expensive doing it that way, but, the way I see it, someone much smarter than me put together those instructions, so I would be wise to adhere to them, and it gives me a lot of peace of mind knowing that it was all done properly and I don't need to worry about it. I'll be picking up an IM gasket set from the dealer when I pick up the condenser tomorrow.

Knight - I tested the knock sensor, and it tested good. You think I should replace it anyways to be safe and eliminate it as a potential problem? Would it test within spec and still be causing an issue?

-Nathan

LongIslandMax

iTrader: (3)

If it tested good, I wouldn't. I tore my knock sensor harness in two when doing other work in my car and it did indeed hesitate until i replaced the harness. However the hesitation was far from what your are dealing with now. Even the fourth gens which are notorious for bad knock sensors never hesitate this significantly before they are swapped out. Don't get me wrong, if all else fails it's a plausible option but I don't think its the culprit of your issue. I still have my money on plugged up precats.

dfj240

iTrader: (1)

Ok, awesome, much appreciated. I'm starting to think you've placed your money in a good spot too mate, because as my options dwindle, the clogged pre-cats still loom. Lol.

-Nathan

Alright, I'm about to head out and pick up the condenser, and run a couple other quick errands this morning, but I was curious and went ahead and tested my front 3 coils (cylinders 2, 4, and 6) and they did test to be good, so that gives me hope that maybe I won't have to replace any coils... Again! Lol. Anyways, I'm going to run and get these things sorted out, and I'll update this again later. Cheers.

-Nathan

MaxPR0908

iTrader: (4)

I dont think its the precats, i have headers and have the same problem..

dfj240

iTrader: (1)

New crank position sensor installed, and new ignition coil condenser installed. No change. I've had a brilliant moment though, and I'm looking into something off the wall that none of us have thought of yet. I'm going to keep you in suspense until I look into it and have a result.

-Nathan

MaxPR0908

iTrader: (4)

Skiped a tooth on timing?

dfj240

iTrader: (1)

Well, it didn't work. Lol. I changed the coolant temperature sensor. It helped a little, and the old one was in a pretty poor state, but it certainly didn't fix my problem. I have been advised to change the Camshaft Position Sensor(s), so I'm going to go ahead and do that.

Btw, on the topic of the knock sensor, if the knock sensor was indeed causing the problem, wouldn't unplugging the knock sensor make the problem go away until it was plugged back in? I have run a car with the knock sensor unplugged and the symptoms disappeared until I plugged it back in. Also, the car had a mild bog when the KS was plugged in, but not nearly as bad as what I'm experiencing with this Maxima. Basically, I have tried running my Maxima with the KS unplugged, and there was no change to anything at all. Any insight on that would be awesome. Thanks.

I'll let you all know what happens with the Cam Position Sensor replacement.

-Nathan

dfj240

iTrader: (1)

Replaced both Cam Position Sensors. No change at all. I also decided to go ahead and seafoam it, and it didn't help at all. I unplugged all the o2's and drove it. Didn't change the bogging at all.

I am now officially lost, and have no clue where to turn next. For all intents and purposes, this car should run like brand new.

-Nathan

Amave

at that point i would be pulling my hair out ^

knight_yyz

iTrader: (40)

I have heard of at least 3 or 4 people who have had serious problems with retarded timing, and even though there was no code for the knock sensor, replacing it seemed to be the problem. Is it possible the harness has a damaged wire? Might be internal.

RR5

iTrader: (6)

Let me see if a long shot can help out.

-Edit well I didn't get a reply to my message.

dfj240

iTrader: (1)

Well, it doesn't seem that there is a damaged wire, and there was continuity between the knock sensor harness plug (the one up near the intake box) and the knock sensor itself. So I know that the wires from the main harness to the KS are good at least. Can't speak for the wiring from the KS all the way to ECU as I haven't tested that connection yet.

That is interesting though. Would a knock sensor cause the car to bog this badly and not rev past 4200? I had one go bad on a 240 of mine, and it bogged a little, but it didn't seem like it bogged as badly as this one is.

I've been out of town for my brother's graduation for the past couple days so I have nothing new to report on the car, but I think I will go ahead and pick up a knock sensor tomorrow and just go ahead and do it. I don't have much left, and I have enough money to take care of all the remaining options, so I'm just going to do all of them. The way I see it, if I end up replacing a part that didn't need to be replaced, then that's one less thing I have to worry about later on.

-Nathan

knight_yyz

iTrader: (40)

hmm, you have fly by wire TB? then it could be the electronic unit on the actual gas pedal. are you bouncing off a ghost redline? My car is doing that right now, and i have a friend with the same problem. he bought a new pedal and the problem is gone.

sontakke

Is it possible that you have got a bum new part?

The only other option left at this point is to have logging scanner hooked up and drive the car and get all the data when the problem happens and compare it with the data when you are revving it at standstill.

dfj240

iTrader: (1)

You know, I haven't checked the circuit on the pedal assembly. I didn't even think about it. I'm so used to having cable driven accelerators. Good on you for thinking of that one. There does seem to be a ghost redline, but I'm wondering if that would cause the bogging that leads up to the ghost redline.

I have tested all the new parts I put on, because I was curious whether I might have put in a new part that wasn't up to spec. Everything tested perfectly, which, actually disappointed me. Lol. I was hoping it was something I could just take back and get a new replacement for and then it would work.

Anyways, new knock sensor is $120, but I'm still hesitant about it. Shouldn't I be able to disconnect it, and the bogging go away as long as it's disconnected if it's bad?

-Nathan

dfj240

iTrader: (1)

Well, I did some research on the pedal assembly, and it has two circuits apparently. The first circuit controls the low input signal, and the second signal kicks in under heavier throttle input and adds voltage to send to the throttle assembly. This could very much explain why I have decent response under light load, but watered down response under mild to heavy load and the car does not have the ability to rev past a certain point (4200 rpms, in this case).

This is all just how I'm translating it, of course, as I am so used to having the simplicity of a cable throttle to work on, but this seems to be a very viable reason for what I'm experiencing. Time to try testing some things and see if I can figure out what's going on, and whether it needs to be replaced.

-Nathan

knight_yyz

iTrader: (40)

I have the exact same problem. If I give it hard I redline at 4200 like bouncing off a rev limiter. If I take it slow i can get past the 4200 mark. It's the gas pedal. A buddy had this happen to him

sontakke

There should a PID in the live data for accelerator pedal position and another one for throttle opening.

You need Sprintbooster :-)

RR5

iTrader: (6)

Check the FSM, ec-304 for the APP (Accelerator pedal position) but I am sure if it wasn't working, you'd have a DTC stored.

dfj240

iTrader: (1)

Hmmm... I don't have a PID for the APP. I've got one for the throttle position opening percentage, but not the APP itself. However, after a quick drive and monitor, the TPS (%) PID will not ever read higher than 50.4%. EVER!

Damn, I wish I had paid attention to that after I replaced the throttle assembly. I knew it was doing that before, but I didn't even pay it any mind afterwards.. Grrrr... Lesson learned. Do any other pedal assemblies work on the Maxima? (350z, Altima, G35, Murano, etc., etc.)

-Nathan

dfj240

iTrader: (1)

Yea, I've read through that, and EC-311 which is also for the APP. If it fails completely then it will trigger fail-safe mode and MIL illumination. However, the APP consists of two different signals and sensors that output differently. As I'm understanding it, if one of the two signals goes bad, it will not trigger a DTC because one of the signals is working properly. If the ECU trips an APP DTC then it will automatically go into fail-safe mode, so I would imagine it would be a trouble code that would take near complete failure to trip the code. That is my understanding of it anyways.

-Nathan

RR5

iTrader: (6)

The FSM is crazy, it repeats the procedures from DTC P0226 for DTC P0227 and P0228.

If you really want to rule out the APP sensor as the problem, start with EC-309. Probing ECM terminals, much fun.

Terminal // Accelerator pedal // Voltage
73
(APP sensor 1) // Released // 0.41 - 0.71V
// Fully depressed // More than 3.7V

74
(APP sensor 2) // Released // 0.08 - 0.48V
// Fully depressed // More than 1.8V

dfj240

iTrader: (1)

Yea, I'm getting ready to do that test. (Oh joy) I'm actually trying to figure the difference between those codes. I can't seem to find anything on the difference between them, but I thought it was kind of odd that could trigger three different codes relating to the APP sensor.

-Nathan

dfj240

iTrader: (1)

Alright, APP sensor test done, and sensor 1 (pin 5 on the connector) is only showing .29 v, when it should be within .41-.71v. So I may have found my culprit. Sensor 2 was within spec and good to go.

Looks like I need to replace it and see if that might solve it. I was curious as to whether or not the APPS could actually trigger a P0300 misfire code, and as it turns out, it can, because sensor 2 is showing that the accelerator is fully depressed so the ECU wants to send more fuel, more air, and produce more spark, and because sensor 1 can't keep up and send the proper voltage to the throttle, there ends up being more fuel, and enough spark to compensate, but not enough air to provide the proper mixture.

Ah, I think I'll spend the rest of the night reminiscing about when cars were made much simpler.

-Nathan

RR5

iTrader: (6)

Wow imagine the problem being so close to your foot!

knight_yyz

iTrader: (40)

The gas pedal from the g or the Z's will not work. The wires are opposed, even though the harness fits, the pedal won't work because the signals are crossed.

I went to a wrecker and found a gas pedal, it was the titanium edition version, but all the rubber nibs were missing. So I just took the electronics off of it. I'll be installing on Monday night. I just finished replacing my passenger control arm and wheel bearing, and finally got the summers on so I am pooped.

dfj240

iTrader: (1)

Hmmmm... Well, let me know if it fixes your issue. I won't even be able to pick one up until after Monday as it is, so I'd be interested to see if it fixes yours. That will probably weigh pretty heavily towards whether or not I decide to spend the money on it. I have already spent more money on parts trying to get this sorted than I did buying the actual car, so I'm a little hesitant to keep throwing money, cause the Mrs. is already giving me hell about spending so much money already.

-Nathan

Blue Mesa

Im not sure I follow your logic. Maybe the FSM says otherwise however I think there are two sensors for safety purposes. I think the ECU compares sensor 1 with sensor 2 , and if the two dont match up it triggers fail safe. I think its to ensure theres no unintentional throttle application, in the event that a sensor goes bad.

A new APP sensor might help considering the voltages arent within spec but I dont think its guaranteed fix.

To be honest though it might not be bad idea to just bring it into the stealership. Granted they arent cheap, but time is money, and so is replacing parts that arent the root cause.

knight_yyz

iTrader: (40)

According to the FSM, the ecu will goe into failsafe mode when it detects a discrepency between the 2 voltages. When in failsafe mode the throttle is forced to only open 10*. So your foot is to the floor and you are accelerating and the pedal voltage doesn't jive with what the ecu expects so it slams the throttle closed to 10* from WOT. Then jumps out of failsafe because the voltages match for a split second so it attempts WOT, then detects the mismatch and goes back to failsafe. It does this back and forth in split seconds until it dawns on you to let off the gas to where the ecu can read proper voltages from the pedal. so that feeling of bouncing off the limiter is the ecu jumping in and out of failsafe mode x times.per.second.

Amave

wait , your car is a 2002 Maxima SE 6-Speed?

those are drive-by-wire setups right?