I have a 2003 Ford Focus with the Zetec 2L, 16 valve. When the car is warm and I put it in neutral or park and take my foot off of the brake it will occasionally shut off. Not stall, but shut off - as though I turned the key. This doesn’t happen every time; it usually doesn’t. I have no other drivability problems and there are no warning lights or engine codes. The ideas I have are:
- vacuum/ brake booster leak
- MAF problem or dirty throttle body
- something weird going on with the transmission shift interlock mechanism.
Just curious to see if anyone has suggestions. Thanks.