Mechanical or wiring problem?
My grand marquis has done this several times this month. I start the car and it starts fine,
engine running, I drop it into gear and engine shuts off and brake and check engine light
come on. This repeats several times . I had it towed once and when we got to shop car
worked fine- showed no problem. Another time I let it sit for 2hours and everything was
Clean the throttle body and check the idle air control valve to see if it needs cleaning or maybe replaced. start there and see if that helps any.
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