About 10 tanks of gas ago my ''check engine soon'' light came on. Our local mechanic downloaded the code and told us it is a vacuum leak. He cleared the code and suggested we see if it happens again. The code check was free and he didn''t have time to do any further diag'' for about a week.


Since then the light comes on everytime we reach 3/4 tank of gas. I pull the PCM B fuse to clear the code. This happens on every tank of fuel....except if I open and close the gas cap after every couple trip....then everything is okay.


Should I just replace the gas cap? Could it be that simple?

 

Morbid curiousity forces me to ask the question what codes are being set?

 

I didn''t record what the code was, but rather took his advice to see if it happened again. He mentioned a check he could do for about $90 that would isolate the cause, but warned that it could come back to be something as simple as requiring a new gas cap. This commnet combined with the timing (always at 3/4 tank) of the check engine light, is what gave me the idea of opening and closing my gas cap about every 1/8 tank. It has worked so far, but I would really like to solve the problem inexpensively.

 

Yes

And yes.