can anyone explain this to me

[79elcamino]

can any explain this to me, friday the check engine light was on and i had a half of tank of gas so i filled up but i went to a different gas station, i went to shell instead of mobil, then saturday night i have a half of tank of gas and i start the car and light doesnt come on, then sunday night i have 1/4 of a tank so i filled up, again went to shell, and i get 3 blocks and the light comes back on, i know i didnt over fill it cause the automatic shut off didnt go off.

[tcope1]

Re: can anyone explain this to me

On a modern vehicle it might be the gas cap is not on tight.

[79elcamino]

Re: can anyone explain this to me

i made sure it clicked at least 3 times, but i will take it off and tighten it again

[SHYNEMAN123]

Re: can anyone explain this to me

If you open the gas cap while the engine is running this will through code and turn on the check engine lite.

If the vent in the gas cap is not working properly same result.

[J. A. Michaels]

Re: can anyone explain this to me

I tend to agree. It sounds like the gas cap is the culprit.

[79elcamino]

Re: can anyone explain this to me

i never pump gas with the engine on and it is a new gas cap, i got it about a month ago and nissan check to make sure it was making a seal

[79elcamino]

Re: can anyone explain this to me

i noticed the vent isnt in the gas cap there it a tiny whole below the gas cap

[Poki]

Re: can anyone explain this to me

The ownes' manual on my Saturn says if the light was due to gas cap not being properly put back on...it can take several fill ups to clear the issue with the light...and it does.....I learned from experience.

[roushstage2]

Re: can anyone explain this to me

What is the code?

[CieraSL]

Re: can anyone explain this to me

i noticed the vent isnt in the gas cap there it a tiny whole below the gas cap

That's a drainage hole, like if you're cleaning that area with the hose and you get water or a little fuel spillage in there - that's what that hole is for.