my mothers 99 lumina(3.1L) had a miss that we took care of today by changing the plugs, wires and o2 sensors(pre and after cat). the care runs beautiful now we figured that this would would turn the check engine light off too but it didnt. my mother told me that when she fills the tank completely up that it will go out for a while but as the tank level drops in comes back. what could be causing this? could it be the gas cap?
the other question i have is reguarding the OBDII system itself. after that light goes out how long if any amount of time does it need to be out before the car would pass inspection?
The misfire code would still be stored inless it was turned off or the battery is disconnected. Are you sure that your mom is tighting the gas cap all the way? This will throw a Evap. leak code and turn on the CEL. But if she has the cap tight and the light comes on when its almost empty id say she has a Evap leak but I have never seen the light only come on after the tank is empty.
take the car to autozone or somewhere and get the codes read for free. Its a guessing game without getting the codes read. But the drive cycles are all different, some MIL will get turned off when the car runs at X amount of rpms for Y minutes, or X mph for Y minutes.
well yesterday we filled the tank up and drove it about 75 miles while we shopped for some things. the check engine light went off shortly after we filled the tank up as expected but hasnt came back on yet. so im hoping the tune-up took care of the light and it just needed driven for a few miles. :)
okay well i have some news. the cars service engine soon light came back on after the car was down to about 3/4 of a tank of gasoline! the car no longer misses but starts kinda hard when its cold. as soon as i get a chance to take it to a local parts store ill get the code checked out. anyone have any insight though?
we figured that this would would turn the check engine light off too but it didnt. my mother told me that when she fills the tank completely up that it will go out for a while but as the tank level drops in comes back. what could be causing this? could it be the gas cap?