Shuts off while driving? I started my car, then it immediately shut down?

HI57

MEMBER
2003 MITSUBISHI GALANT

I started my car, then it immediately shut down. No power at all worked. I would let it rest, then try to start it again, but again it would immediately shut down. Called AAA to check the battery and they did test. Results were everything was fine except the battery need to be replaced. So, they replaced it with a new battery. Now the car starts and I could drive it, but it would still shut, down when I'm driving. I think it would stop when I wouldn't use the pedal. So, what is the problem?

2 Replies

CARADIODOC

MECHANIC
33,908 POSTS

Hi HI57. Welcome to the forum. I answered the same question for the same model just yesterday and it seems to have solved the problem. I wasn't sure because my reply was for a Chrysler product. (Mitsubishi and Chrysler have a lot in common).

If your engine will continue to run as long as you are pressing on the gas pedal, (there are no other stalling problems), the problem is most likely just related to the battery being disconnected or run dead. The Engine Computer loses its memory. Until it relearns "minimum throttle", it will not know when it must be in control of idle speed so it will allow the engine to idle too slowly and stall, particularly at stop signs.

To meet the conditions for it to relearn minimum throttle, simply drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the brake or gas pedals. At that point, the computer will memorize the voltage from the throttle position sensor. From then on, every time it sees that same voltage, it will know your foot is off the gas pedal and it must be in control of idle speed.

Caradiodoc