I am working on a friend's 1999 Maxima. Currently I told her to go out and get me some CRC MAF cleaner, but I have question regarding the MAF.

Her car runs rough, or feels like it's missing at times. This can be at idle, or around 2500-3000 RPM when she took me for a drive. I could feel hesitations/missing/light bucking.

I had her start the engine, and I disconnected the MAF. I expected the engine to run smoother, if it was an MAF problem, but instead the engine just died. I plug it in and it fires right up again.

Any ideas?

 

prolly bad ground to maf do u have some one u can swap a maf with to see if it runs better

 

Yeah try the MAF first. Also the sputtering and hesitation could be coil packs..

 

I'd check her MAF first, then check coil packs and spark plugs.

 

I need to talk to the other person that worked on her car. The best info I could get out of her (non mechanic speak), is that the coils and plugs were both changed out

What I still can't figure out is why a car would die after the MAF was disconnected. I thought if the MAF was bad, it would run WHILE connected, LOL not the opposite.

@Trini - Mine is a 2K, so I have a different MAF. I'm hoping she gets that cleaner soon as well.

 

I have a similar female friend though she has a 5th gen and her idle is rough, jumps from 700 to 1700 rpm constantly. Supposedly, she just replaced her throttle body and it didn't fix her problem.

 

prolly her iacv

 

When the maf is taken off the ECU can't process how much air is going through, that's why it shuts down.... But definitly clean the maf sensor and clear any debris from it and also clean the throttle body. If that doesn't cut it then start checking coils

 

+1

Once you unplug the MAF, the car should run a lot worse or not at all. If the MAF is faulty, the car may still run but will jus send bad signals to the ECU. '

Def clean MAF and TB per how tos. CHeck IACV and check ground on the MAF and its harness too

 

Ive always heard and been told to never clean the maf even with "MAF cleaner" it can actually cause more damage. If you need a MAF though PM i have one for pretty cheap

 

tell me more about that lip!!! I don't feel like paying for a Stillen Lip! email me at jonshivprashad@yahoo.com

 

Ok I guess that explains why it died. I'd ready on another forum (I thought here), to "unplug the MAF. If it runs smoother, it's the MAF" Hence I could not figure out why it died when I umplugged it. Odd/Bad advice earlier possibly.

Thanks everyone!

 

Jus need to be gentle and not drown it. I have cleaned MAFs on 3 different maximas and never a problem. But i think if the wire element is loose then yea u prolly dont want to spray pressurized cleaner on it