[digplants]

2002 Turbo NB
I have noticed this past month or so that my Check Engine light will turn off when I hit about 1/4 mark on my gas tank.

This doesn't always happen. However, Earlier this month after it did happen, I filled my tank and waited. Sure enough it happened again.

I have tried a code reader and ended up lost in hopelessness. I have the results somewhere, perhaps even in another thread, but the despair came from all the possibilities.

SO I guess what this particular thread is regarding is:

Is there anything I should check with this new data?
Anything gas tank related to check engine lights? (I know thats a huge bucket of worms im asking, but maybe theres some shining ray of hope.)

One last thing, My gas cap seems to be the original, and i have inspected it over and over, cant seem to find anything wrnog with it, but it doesnt have that attachment on it to keep it on the car, so it has seen better days. The ring inside however seems fine.

Thanks for any and all responses!

 

[Smileybug]

I would get the code(s). That will really help us out.

 

[red99]

2002 Turbo NB
I have noticed this past month or so that my Check Engine light will turn off when I hit about 1/4 mark on my gas tank.

So, the check engine light is on when you have more than 1/4 tank of gas and off when it is less?

 

[digplants]

yeah, and the codes are..

17559 - Long Term Fuel Trim Additive Air; Bank 1; Range 1: System too Lean
P1151 - 35-10 - - - Intermittent

and the seat-belt one but is irrelevant in this thread.

 

[jfoj]

Lean codes are likely due to vacuum leaks, MAF issues, fuel pressure or volume or could even be an issue with O2 sensors.

How does your car start and idle?
Do you have any freeze frame data to back up your codes? What does this freeze frame data show?

Does the CEL come on at idle or while cruising??

What are your fuel trims and O2 sensor behavior and engine coolant temperature?

Have the small black and white vacuum check valves under the engine cover ever been replaced? These are famous for breaking down and leaking on these engines.