Engine Performance problem
1996 Nissan Maxima 6 cyl Two Wheel Drive Automatic 195000 miles
About a year ago, my car started idling rough. It would shudder when I was idling. After a few months it started idling so rough that it would die. The only way to keep it from dying was to give it gas while stopped. It didn't shudder if I put the car in neutral or park. The problem only existed when in park, reverse, etc. After researching, I replaced the mass air flow sensor. This fixed the problem. After about 6 months the same problem started again. It continued to get worse until it started dying again. I bought another mass air flow sensor, installed it, and it didn't seem to help. I took it back and swapped it for another one, just in case the first one was bad as I was purchasing remanufactured mass air flow sensor and not new. So, after putting the second sensor on since the problem came back, I'm not sure that the sensor is the problem this time. What else could it be? The symptoms are no different than when I changed the sensor and it fixed it temporarily.
Is the Check Engine Light indicating and have you tried retrieving for trouble codes?
If the problem is only poor idling and does not affect the performance while driving, the problem would more likely to be the idle control system rather than the MAF.
I would suggest getting the Idla Air Control valve and throttle body cleaned and retest. Carb cleaner is an efficient cleaning agent for the above components.
July, 8, 2010 AT 3:00 PM
The first time I had trouble with this a year ago before ever changing the MAF my check engine light was on. It came back as engine speed sensor, which I changed and it didn't make a difference and I believe the other code was Knock Sensor Bank 1 which I didn't change. As of now, I don't think the check engine light itself is working. When I turn the car on, and all the indicator lights light up to show they work such as the oil light, the check engine light doesn't come on. I did forget to mention in the original post that when taking off from a stop there is a hesitation in the acceleration. I hit the gas pedal and it takes a few seconds before the car will do anything other than kind of putter along. Also, if the car does happen to die because I'm stopped and not holding the gas while I'm stopped, when I try to restart the car I have to give it gas to keep it cranked, usually having to put the car back in drive while giving it some gas. Do you still think it sounds like the idle control system? Any ideas as to why the MAF sensor being changed the first time helped? That was my main concern. Same exact symptoms, one time it fixed it and now it won't. Thank you for your time and help!
July, 8, 2010 AT 3:20 PM
The additional symptoms indicates the MAF or throttle position sensor to be more likely cause.
Since the CEL is not indicating, it could be a fault with the circuit or the PCM itself.
Get the codes retrieved and let me know the exact code so we can understand what could be causing the problem.