Lincoln/Mercury Repair: 1999 Mercury Sable Idle, mass air flow sensor, mass air flow

Question
The car got rear ended about a week ago and now problems have risen up.  First, the car had problems starting.  You would turn it over and it would crank and sound like it was going to start, then it would just turn off.  After about three times it started and stayed on.

Just recently while on the freeway the RPM's dropped significantly, about 500.

Finally, after getting off of the freeway today the RPM's stayed around 2000 and while coming up to a stop light I pressed the brakes and it still wanted to keep going.  Once it was put into neutral the RPM's continued to be high.  Please Help.

Answer
Hi Tim,

This is likely a sensor problem. Could be an O2 sensor if the exhaust was affected in the crash. I think though, you'll find it to be a MAF (mass air flow) sensor. I suggest you take it to your nearest Cottman transmission and they will scan your car for codes for free. I understand that Aamco transmissions is doing this free now also. Once you have the code number, resubmit to me and I will fully and cheerfully explain the repair for you.