RE: How long does the comp take to reset(MAF) change
I assume you mean you had a check engine light, determined it was the MAF, have replaced or cleaned it, and now you want to know when the CE light will go out, assuming the problems is resolved? The answer to that is approximately 20 start-up/shut-down cycles of the engine.
RE: How long does the comp take to reset(MAF) change
IIRC, it took less than 6 starts to clear the Check Engine light on the 98ML when I changed it last year.
Dealer said I had to come by for a "reset" / reboot but I didn't have to do that. The car has been into the dealer twice since the MAF swap, and definitely on the OBD last month to check the failed crank sensor. No fault codes came up.
Oh, I bought the MAF new off eBay for $125 and it took less than 15 minutes for the re & re. Dealer quoted $900 including 2.5 hrs labor!!!
RE: How long does the comp take to reset(MAF) change
Keep in mind that a MAF failure is not necessarily “absolute�. It can begin as an intermittent problem and only registers one fault under a certain condition (i.e. RPM, ambient temp and humidity combination). If this is the case, it’s possible that you could restart the engine 15 more times without a fault, then replace the MAF, and it would only take 5 to clear the error code.
RE: How long does the comp take to reset(MAF) change
When I replaced my mass air flow, it took three on-off starts to clear the code from my computer. An on-off start is usually classified as a start and drive for about 10 minutes each. The computer has to make sure that theproblem has been corrected before it will clear it.