When my tank goes to half full, my CEL comes on. Fill the tank, goes off. Repeats every time. What could it be?

07 TL-S

 

weird i just made a thread right now cause my CEL comes on when my low gas light comes on. lol

 

Yea, I see that. WTF could it be?

 

Dunno but i think urs is a little different than mine cause u said ur cel goes off when you fill up. Mine doesnt lol i dunno maybe bad fuel pump?????? i dunno but someone can prolly figure it out here. Did u check what codes u got from ur CEL?? mine are all misfires

 

Didnt check the codes, I think Im gonna have to take it in to the dealer. Doesnt make sense to me.

 

I would avoid the dealer diagnostic fee and take it to autozone/o'reilly's to pull the code.

 

ya bro pull the codes i wanna see if it shows misfires like my car. also what kind of gas do u put in ur car?

 

Wouldnt pay the dealer crap. I just bought the car less than a year ago from them. Second problem with this car in less than a year, and its pissing me off. If they tried to charge me, I'll throw a bitch fit so loud and long, they will fix it just to get me out of there.

As soon as I get the light again, (just filled up), I will stop by auto zone to get the codes. I use shell 93 octane in my car, which seems to make it run the best (at least in my head it does).

 

lmao but yea same here 93 v power from shell

 

You guys need to buy a simple $50-60 obd2 scanner...in fact I think every obd2 car owner should have one lol... it saves so much time and headaches. Pull a code, look it up, clear it (resets the ECM, without having to do the battery disconnect and all that crap)
You can diagnose your own car in an instant.
I can't drive without that scanner.

Back to the subject...
Having some codes would help telling you what's wrong.
To the OP: That could be an indication of something wrong with the the EVAP. Fumes in the tank increase with lower gas levels. When you fill it up, not so much.

Yonkers..You also need codes...if misfire codes is all you're getting, and this happens when you run low on gas, it could be you're fuel pump losing pressure.

 

thanx Opel i was thinking fuel pump think ima switch it out ya i need to buy a scanner just being cheap lol

 

I took it to advanced auto and I got a P0401 code, Insufficient EGR flow.

Had this same problem with my honda accord, and it was due to so much carbon build up. I bought a gasket for $1.49 and cleaned out the carbon under the egr valve as much as I could. Time will tell if that worked.

 

I have the same misfire codes as you yonkers. Mine seems to only happen at idle. Im hoping someone had the same problem on here. Let me know if you figure anything out. Im thinking about changing out my coil packs.

I changed my spark plugs and the problem seemed to go away for a little while but now is coming back even worse.

 

k ill keep u updated if i find out anything new and ya i got new plugs but same problem

 

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It's NOT in your head, you ARE getting better throttle response.
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