hellpp please, engine turns off by itself Options

[immortal]

hello boys
i have a 98 jmd celica ss3 and i have a big problem and i am wondering if you can help me
basically when my car reaches its normal temperature and i am stopped in traffic lights the rmp is going up and down and after few seconds my engine turns off itself
did anobody have the same problem before?

[azian_advanced]

yes, you may have a faulty coolant temp sensor. mine was faulty and i was getting a low idle.

what happens is since the coolant temperature sensor isn't reading the temperature (seeing that's it's faulty or broken) that the ECU uses a fail-safe temperature (probably around 40 oC) and assumes the coolant is at that temperature (which really is NOT). and because of that, you would get a low idle.

usually this is the case during a cold morning start-up but this shouldn't be the case if your engine is already warmed up.

i'm guessing your injectors may need cleaning.. because if that's the case, you'd get anywhere between a low idle to a normal idle.. and bounces up and down in that range. if that's the problem, just take your car to a mechanic and have the injectors cleaned, or buy a bottle of the injector cleaner which is only about $6