Didn't get much response on the noob thread but I finally can post!

I used these forums a ton back in the day but all has been quiet in my Maxima world. Maybe that's cause its been parked for two years from the stalling issues that so many seem to be having. I lived in Missouri at the time which required inspections and since it died at every red light, I never bothered. Now I live in Alabama. No worries! Except it drove like crap.

On my first test run, I started hearing a hissing on acceleration. I jacked it up and found an exhaust leak. I patched it enough to get to the exhaust shop. Could this have been the problem all along? maybe now it was just so bad it was really affecting things? Mechanic recommended also replacing catalytic converter. $250 later and I stalled at a red light shortly thereafter. Of course it wasn't that simple; at least the car would drive at all again.

So I came back to my trusty maxima.org forums. I saw all the great stickies and had always heard from folks to check the IACV. Sunday I was bored so I decided to get some throttle body cleaner and go at it. I took the IACV completely off, and undid the throttle body somewhat so I could clean most of the gunk without undoing all of the hoses on the bottom.. Since it was Sunday, I had no new gaskets so those stayed the same.

Boy was I excited at all the crap in the Idle ACV... cleaned it up like new. Got it all back together and it ran pretty decent. Til I test drove it for a while. Eventually it was still dying occasionally. Not at every red light anymore at least.

I adjusted my idle to 900 rpms in park and its at about 600 in neutral or drive. There is a bit of hesitation somewhere between first and second gears but the main issue is stopping at a light and it dropping to 200 or 300 rpms. Since cleaning, it will drop and not always die.

Took it to autozone today and got:
P1441 an exhaust code they told me I'd need the dealer for more info
P0325 knock sensor
P0130 Bank 1 sensor 1 o2
P0732 something about the 2nd gear ratio

I've plugged these in and read all I can understand about them. I'm hoping the tranny code has been caused by either the slightly low tranny fluid or one of the hiccups from the stalling and exhaust issues. Before I had the leak fixed it would not even find the gear sometimes.

From what I read, the knock sensor is sometimes triggered by other codes so I don't think I should do that yet.

Tonight I got all excited to read about MAF sensors and how they are so many people's problem. I left the library to go outside and unplug it, and when I wiggled it, the car died. I unplugged it and started up but the idle is still inconsistent, varying from 800-1100 rpms. So I'm worried this may not be it.

I have the new fuel filter on the way but thats just a precaution cause it set so long- I shoudl be so lucky that its that simple...

My question... where do I start? I bought the gaskets for the IACV and TB and I thought I would clean the EGR tube? I bought those gaskets too. But if that is not likely causing my stalling, I don't want to get in there.

From what I read, O2 or knock sensors are probably not causing the stalling.

How should I proceed? Thank you so much for helping me!

Dom

 

I think you have a flakey MAF sensor. When you go to fit your new gaskets look at the thin wire in the MAF sensor. Is it clean, is there visible build up on it. CRC makes a MAF sensor spray cleaner availabe any reputable part house. If you clean this wire do not touch it with your fingers or the spray straw, it is ubber sensitive and fragile. I still think your MAF sensor is your issue. If your O2 sensors are throwing a code they could be contributing to your stalling as well. As these should be a feedback looped tied to air fuel management. The knock sensor from what I understand is really only a predetonation protective device for the motor. Normally if it goes out your mileage will go in the tank as the timing gets retarded to preserve the motor. The KS is also a known suspect part on these motors.

Fix your code issues or reset your ECU and see what if any new codes get thrown.

 

I wd start with Cleaning MAF with MAF cleaner, clean TB and IACV. THat might get rid of stalling. REplace o2 sensor too. Exhaust could be reason for stalling. Cat might be plugged with debris from rotted upstream exhaust pipe.

 

One thing to be aware of. I was told my MAF was shot and at the time I was 500 miles away from home and had no choice. It cost me $600 only to have the problem return shortly after returning home. It was actually the wires to the MAF sensor that had cracked. A lot of stalling issues, especially when stopped, mean that the air/fuel mixture is off. Since you said that the IACV was so filthy it sounds to me that you are running rich, ie not enough air. It would be a good idea to clean out the EGR tube as well, being that it's where the gunk comes through to get into your IACV.

 

Thanks everybody!

I bought the maf cleaner the other day so I'll do that really soon. You mentioned the wires and I thought it was odd the car died when I touched the plug, long before it was unplugged. Is that normal? It made me wonder if it may be a connection issue. The connector itself is clean.

I was also unaware the egr was before the iacv. I thought it was the other way around. I guess I'll suffer through that hacksaw blade and bolt ordeal.

I'll see how it does with those things and the fuel filter then take it from there. I'll do the o2 if it's a possible culprit but I really want to solve the stalling problem before I work on other stuff.

Dom

 

So...

Things were getting better but still some stalling. This weekend I had time to change the fuel filter and use the MAF cleaner. I was kind of afraid I broke the MAF sensore because in the how-to it didn't mention it having the four screws on it. I took them off and was afraid I broke some connections inside. Too late to change anything, I sprayed cleaner in it, and all in the tube and on those two little wires. Also sprayed it in some holes that went to vacuum hoses and all kinds of soot dripped out.

I let it all dry and reassembled and it seemed ok. I drove it around for a few hours with no problems. The idle is not super steady but pretty close. I have also used two bottles of Chevron Techron.

I took it to Autozone and had the codes cleared. At the time, I had all 4 from above plus a code for the MAF which I never had before.

Yesterday, I checked them and all that was on is P1441 and P0325 for the knock sensor. The O2 code has not shown back up yet. Is it possible the sensor is ok but the other problems caused a fault? Or does it just need more time to come back on?

Should I go ahead and tackle the knock sensor or could this P1441 be causing it? Vacuum Valve Bypass. I've done some searching on it but have not found my answer.

Thanks for all the help so far, what should I do next?

Dom

 

cant someone point me to the thread on HOW TO clean the MAF and TB

 

http://forums.maxima.org/4th-generat...g-dummies.html

But as i stated above, I'm not sure if you take the four screws off the MAF sensor- can someone shed some light on this?

 

So my car is doing the same thing. Three or four weeks ago I did the MAF clean and took the sensor off the wrong way. Well long story short you are suppost to disconnect the wire, then remove the MAF plastic tube from the air box(4screws) and on the other side into the engine.

Basically if you ripped the MAF off where the wires go in by pulling out those 4 screws...you messed up like I did--getting over excited and not rechecking the .org for more info. I did the 300zx filter and busted right in on the MAF. Well after I broke that, I took it all off correctly and removed the plastic top square using a utility knife. This exposed a brass plate that is removable and underneath are circuits where the plug goes into. The plug I ripped out has three prongs which connected to the MAF, so I soldered them back on to the circuits in the MAF square and used liquid electrical tape to seal up the top square of the MAF.

I reassembled it all, it has run fine for 2.5 weeks or so---BUT is acting up again as of yesterday... I am really thinking it is the TPS, b/c it lull's or hesitates at low rpms, and sometimes when i push in the clutch betw. 2nd and 3rd.

I have yet to do the IACV and TB clean out, going to order the gaskets and do them with the EGR in one swoop in a month(maybe sooner if it acts up constantly)! Also need to check the coils when I do the plugs shortly too. I was thinking of wrapping the coils in electrical tape like i've heard mentioned on the .org in the meantime. Oh an in the near future, order a new MAF...

 

I thought the sticky was golden. It detailed every step but the actual cleaning of the MAF. I searched for twenty minutes and never found any directions about those screws. My only internet was on an iphone so eventually I figured, Hey, it has screws, they must come off. I definitely undid some connection but now the car runs great. I'm hoping I don't hit a bump and undo it all..

 

I answered in the other thread....

But yes, remove the 4 screws on one side of the MAF. Then loosen the clamp on the other side of the MAF. MAF shd twist off.