My car has had a very erratic and scwred up idle for quite some time now, the idle will drop down to around 300RPMS then back to a 1K rpms then settle and the car stalls every once in a while, So far I have replaced the ICV and that did not help at all, the idle is so bad I can’t fix it I’m going to sell the car. When I disconnect the MAF sensor and drive it the problem is fix, the car runs perfect, well the idle issue is completely fix when it’s disconnected but as soon as it’s reconnected the idle problem reoccurs and it has slowly been getting worse. I have a ECIS intake so I think some old got on it and messed the sensor but, I wanted to get some input to make sure my assumption that the MAF is bad.
RedBarron
- Status
It could be your MAF, but I would try to swap in a "known good part" before buying a new one. The reason is that when you disconnect the a major part like the MAF, the DME sees that it is not there and can put the engine into a failsafe mode where it may ignore some other sensor readings or change certain outputs.
As an example, I was diagnosing a car that was setting misfire faults under specific rpm and load conditions. I disconnected the MAF, drove the car, and no more misfire faults. I swapped in a known good MAF and the faults came right back; I'm guessing that with the MAF disconnected, the DME simply stopped looking for misfires and just focused on making the engine run as well as possible without an important sensor.
Do you have any friends with a MAF you can borrow?
If the MAF doesn't fix it, and there aren't any faults stored for cam sensors or apparent voltage supply issues, I would take a look at the VANOS adjustment unit, especially if you have high miles and/or the symptoms happen mostly when the engine is cold. Good luck!
As an example, I was diagnosing a car that was setting misfire faults under specific rpm and load conditions. I disconnected the MAF, drove the car, and no more misfire faults. I swapped in a known good MAF and the faults came right back; I'm guessing that with the MAF disconnected, the DME simply stopped looking for misfires and just focused on making the engine run as well as possible without an important sensor.
Do you have any friends with a MAF you can borrow?
If the MAF doesn't fix it, and there aren't any faults stored for cam sensors or apparent voltage supply issues, I would take a look at the VANOS adjustment unit, especially if you have high miles and/or the symptoms happen mostly when the engine is cold. Good luck!
the thing about a bad MAF is that it will usually give you a CEL. You might want to check your engine for vacuum leaks around the intake area - a lot of people seem to have a cracked rubber boot that connects to the intake manifold. I checked mine on my 01 and it has the beginnings of cracking.
- Status
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
