Check Engine Light - BMW Forum

komodo · 08-18-2004, 11:03 PM

I stopped by autozone today and had them pull my check engine light code. Assumingly there is a leak somewhere in my fuel system. They suggested the gas cap, but I just changed that a few weeks ago. What else could it be? I don't smell anything and nothing is leaking from under the car but the a/c.

Any ideas? :

Cruzin 323is · 08-19-2004, 12:43 AM

u don't need to change the gas cap.. u just need to make sure its close all the way.. if thats not it.. they need to hook your car up to the computer and run a diagnostics check... could be an air sensor....

LivinFast67 · 08-19-2004, 01:32 AM

my gas cap lock works, it locks when the doors lock, but i have to have the doors unlocked to get in, and the cap swings out about half an inch when its not bolted. do i have to re-hang it on its hinge to get it to stay closed when i'm done filling up, or getting in and out?

Fadec40 · 08-19-2004, 06:39 AM

The gas cap causing the check engine light to come on is notorious on the BMW. I went to Mitchell on demand and it is an ongoing problem with this car.
What I have done is put a nice wad of petroleum jelly on the gas cap seal. So even if the gas cap is locked and a small fuel pressure leak is caused by the gas cap itself, the petroleum jelly fills whatever slight gap might be there when the cap is secured .

I have been doing this for quite a while and NO check engine light has come on. It came on again after I first did it. But that was about three months later and noticed most of the jelly was gone, so I reapplied it.

Just a suggestion.

komodo · 08-19-2004, 09:24 AM

Quote:

Originally posted by Cruzin 323is@Aug 19 2004, 01:23 AM
u don't need to change the gas cap.. u just need to make sure its close all the way.. if thats not it.. they need to hook your car up to the computer and run a diagnostics check... could be an air sensor....

I know, and either way I just did a few weeks ago. I'm asking what else it could be

325isBaby · 08-19-2004, 09:04 PM

Anything Emissions related will set a check engine light.

NyteRyda · 08-19-2004, 10:04 PM

i have the same problem with my car. i have heard that the check engiene light can come on if something is wrong with the cat convertor. Hopefully the tip on the gas cap is right. I am going to tightly close my gas cap later and see if it gets rid of the annoying check engiene light.