All,

I've been searching this forum for a while on this issue and can't seem to scrounge up any info on this topic. From all the maximas that I have owned, these cars are very smooth running and I should barely even be able to feel this car when it is on. What happens is occasionally (when warm) the car will feel like it has a very slight miss at idle. The only way i can describe it would be as if a coil pack went dead, but not nearly as severe (I have had that happen already). It's just enough to **** me off and not cause the car to throw a CEL. Has anyone had this issue? It has to be something electrical because there are other times that I come to a stop at a light and thing is running flawlessly. Here is what I've done so far to the motor:

- All coil packs and spark plugs replaced with OEM Nissan parts
- All injectors OHMed out fine and I've probably ran about two cans of SEAFOAM through the gas tank to rule out a clogged injector.
- New upper intake gasket
- All vac hoses gone over and seem to be fine.

I'm out of options and started to realize that I might just have to live with this. Car has 90K on it and has been in a low to moderate impact on the driver side front (not sure if that matters).

Please help,
Nick

 

Nothing guys? I was thinking maybe IAC valve or MAF sensor? Anyone has this problem?

 

I'm looking for answers myself...Did coils, plugs, intake gasket flushed injectors...Car runs perfect at times but then it will act up randomly out of nowhere. 3 shops and still not fixed.
1 shop did say the valves may be bent or leaking causing that problem. also, the Catalyic Converters might be sorta clogged...

I've had enough..I just dropped it off at the stealer to get a second opinion.

 

Well it's good to hear that it's not just mine. I was thinking about making my own homemade grounding kit and seeing if that helps anything. Next would be MAF and then I'm done throwing money at this problem. Please keep me posted on what the stealership has to say as this may be a known problem.

 

i will let you know what the guys at the dealer says. stay tuned

 

Surren - any luck at the dealer?

 

My wife's 2003 maxima has this problem and it pisses me for everytime I drive it. I haven't started to throw money at it but I am ready too. It feels like a random misfire every 10-20 seconds while the motor is warmed up at an idle at stop lights. No check engine light has every came on.

 

try changing the pcv valve located on the rear valve cover near the firewall. the manifold will have to come off in order to do this replacement. good thing the part cost about $8.00

 

Same exact issue I've been having for a long time. The car drove fine for about a month and then it came back. Mine will do it in gear or neutral at a stop. I've noticed whenever it happens, if I try to accelerate with more than 60% throttle it will stumble hard right around 4.8k rpm. This problem always gets worse in the summer time in my case also.

 

Same problem here Nick.

I have a code P0301 but this code did not appear until after my intake manifold was installed. I also got new plugs since the manifold was already off. I don't want to speculate about your issue, but mine is listed as a cylinder #1 misfire which includes the possibility of a bad injector, coil or spark plug. The possibilities also exist for poor cylinder compression (bad head gasket, leaky valve stem seals, bad rings), defective coil pack, worn/broken/fouled spark plug, bent valves. However, my car has 154,000 miles on it. I hope this helps,

Good luck!

 

I had this problem with my i35 and it happened to be the camshaft sensor, the one on the radiator side of the motor were the tranny and engine connect. hope that helps. its black and its like a magnet. i had also replaced my coils and spark plugs but changing the sensor made it go away.

 

Annimax - I would think if this was a mechanical problem that it would be happening constantly, correct? Not erratically?

Mik2006 - How many cam sensors does this car have? I would assume multiple since it has 4 cams? Easy to replace?

CXJ - What is your theory behind the PCV valve? I think I can replace this without removing the upper plenum.

 

1 heres a lil pic. I did not even have to jack my car up but heres a pic its the bottom right one. and its the black sensor that has one screw and its in between the transmisson and engine.



hope this helps.

 

Crankshaft sensor?

 

I would try the crankshaft sensor. if that isn't it try to clean the MAF sensor and throttle body. I did the last 2 and it fixed my my misfire issues.

 

Aren't there two crank sensors on this car?

 

Understood. However, you did initially describe your problem as occurring when your car is warm at idle. My problem is similar to yours as in I feel the misfire during idle and I also got the P0301 code that I mentioned so I made my suggestions based upon the similarity of our dilemmas. Just for reference, one vehicle I researched to find your answer actually had an incorrect spark plug gap causing his misfire (will provide the link if you desire). I'm not suggesting that that is your problem since his misfire also occurred during acceleration, but I would not be too quick to rule it or other mechanical problems out only because heat changes tolerances and the engine will behave differently warm than cold especially where problems exist.

 

The problem could very well be present when its cold but due to the idle being higher, I don't feel it. I gapped all those plugs to .44. Correct? I'm going to try the PCV this weekend cause its cheap.

 

Hey man i signed up when i saw this post and I have an answer for you if you havent already figured it out. Sounds exactly like what my car was doin and i changed tons of stuff before i finally fixed it. It never threw a code for me but i knew there was a problem, and once fixed i felt like i had gained 100 hp, and went from a plymouth aries to snatching 3rd gear.

So About 2 months ago I bought a 2005 Nissan Maxima SE , the car was perfect all around except for one problem, felt like i was lacking a lot of power especially around 4800 rpm, with more than half throttle exactly like you described. It was not fast, but performed much better low-end. I suspected the vias for the longest time, i thought for sure that the power valve wasnt opening back up past 3600 rpm like its supposed to until one day i suspected the MAF so researched it. I saw someone say to check it unplug it and if it runs better then its bad, so i unplug it and take off, but couldnt pass 2500 rpms and then the CEL popped on so i pulled over and reconnected , then was on my way home to clear the codes, when i noticed it was running much better since the engine light came on. I assume when it threw codes for the MAF and IAT sensors it must have changed the A/F ratio making it run better. Finally!

So i guess you could try diagnosing it by unplugging the MAF and forcing it to throw a code, then plug it back in to see if it runs any different, or you can just go get you a new MAF because thats definately your problem, Im no pro, so some of my info may be wrong, but i do know for a fact that I had a bad MAF that did not throw a code. Hope this can help someone

 

Ruled out PCV. By the way, this can be done without taking off the upper intake. Just takes some finesse.

 

You get a chance to try out the MAF sensor or throttle body yet??? I'm having the same misfire and I'm pretty sure my air/fuel ratio is off an causing an issue somewhere. Let me know how it works out, any possible solution is appreciated

 

I'm on the verge of purchasing a new MAF so I'll let you know how it goes when that happens. I was leaning towards the crank sensor but the more I search, it seems like a crank sensor would be more likely to cause a no start situation. I unplugged the MAF this morning, started it so it threw a code, shut if off and plugged it back in (in hopes that it will relearn the A/F mix) so we'll see how it is on the ride home from work today.

I don't want to touch the TB as I've read horror stories from people that do this on a drive by wire TB. Plus I really don't understand how a mechanical valve can have anything to do with a rougher than normal idle. I can see a high or low idle being the result of a bad/dirty TB but not a rough idle.

Also, does this this car have two MAF sensors?? A few sites I've seen state there's possibly a lower (the one i'm used to by the air filter) and an upper?

 

Idle re-learn helped this problem a bunch but not a complete fix. I will clean the IAC first and then on to the MAF sensor.

 

OK. So apparently this car doesn't have an IAC like my '00 did. Can someone please confirm this for me? I have a feeling it's embedded in the throttle body (not a separate unit) and I don't have the cash to be investing into a new one of those.

 

Replaced the MAF last night. I instantly noticed better idle when I first started it this morning. After an hour of driving I could feel a slight vibration, but it seems to be better. However, I've had this happen before so I'll let it go through the drive cycle for a few days and report back.

 

ok

 

any updates?

 

I wanted to bring up this old thread for anyone having this problem. Finally got a code for the EVAP valve being stuck open P1444. Took off the valve, cleaned it out so it was functioning properly and bam (was not spending 100-150 on a new valve). Car runs like glass now and my gas milage jumped 2 points. This is the first time that I have ever had emissions equipment play a role in the drivability of any vehicle I have owned. Live and learn.

 

I finally had one of my coil packs start to die out. When I first started the motor it would miss really bad for 2-3 seconds 2-3 times in the first mile of driving. It was random and never bad enough to throw a check engine light. I friend had three brand new coil packs so I put them in the front bank to narrow down the misfire problem. AND IT FIXED IT!!! one of the coil pack was causing the intermittent idle miss and it hasn't done the missing at start up since I changed the 3 coil packs.