idle surge
11-18-2008, 07:36 PM
#16
Rennlist Member
If you have an S4 that won't run when the MAF is disconnected, then something besides the MAF is wrong with the car. ....that being said, a pristine MAF could very well coverup or otherwise compensate for a non-MAF problem. In that case, replacing the MAF could give the illusion of fixing the car (even though the other problem remained).
11-18-2008, 09:52 PM
#17
Nordschleife Master
no doubt,
I do agree with you to a partial extent. But anything even a slight inconsistancy in the LH, or abit of corrosion on a ground could prevent it from be able to run without the MAF. On the said car, the ONLY thing that I did not verify was in perfect order was the hall sensor for the camshafts. Everything else that might have had an effect on it specked out perfectly, TPS, Temp I/II, O2 sensor.
Now I haven't confirmed if it is possible or not, but if the LH learns with a bad MAF and takes a map from that, then you disconnect the MAF, it possibly could be too far out of normal parameters to run, but that would be abit of a long shot imo.
As well we are dealing with 20+ year old cars. To be fair nothing is going to be like it was coming out of the factory and there are way too many variables that we really could not account for.
I do agree with you to a partial extent. But anything even a slight inconsistancy in the LH, or abit of corrosion on a ground could prevent it from be able to run without the MAF. On the said car, the ONLY thing that I did not verify was in perfect order was the hall sensor for the camshafts. Everything else that might have had an effect on it specked out perfectly, TPS, Temp I/II, O2 sensor.
Now I haven't confirmed if it is possible or not, but if the LH learns with a bad MAF and takes a map from that, then you disconnect the MAF, it possibly could be too far out of normal parameters to run, but that would be abit of a long shot imo.
As well we are dealing with 20+ year old cars. To be fair nothing is going to be like it was coming out of the factory and there are way too many variables that we really could not account for.
11-18-2008, 10:03 PM
#18
Rennlist Member
But I think air temp is really intake air temp, which I think is measured by the MAF. Some speculation here... can anyone confirm or deny??
11-19-2008, 03:54 AM
#19
Nordschleife Master
yes air temp is the intake air temp,
the MAF reads the amount of air by the air which passes over a platinum wire, which has electricity passing through it. less air cools it less, creating more resistance and less voltage. (simplified abit :P )
As well Tom, I saw your other thread.
Some of that info would have been good to let us know in the beginning of this thread. And is the same issue. In the future common edicate dictates that one would keep everything pertaining to the issue in one thread instead of creating a second thread on the same issue.
the MAF reads the amount of air by the air which passes over a platinum wire, which has electricity passing through it. less air cools it less, creating more resistance and less voltage. (simplified abit :P )
As well Tom, I saw your other thread.
Some of that info would have been good to let us know in the beginning of this thread. And is the same issue. In the future common edicate dictates that one would keep everything pertaining to the issue in one thread instead of creating a second thread on the same issue.