Need Help!! Check Engine Light.

[jawsofire]

My check engine lights keeps turning on when I drive at high speeds. It turns off after a day or two of low speed driving. By high speed I mean over 60 mph. I'm getting a lean mixture code. What can it be?

[speedy25]

When was the last time you changed your fuel filter?

-SP

[jawsofire]

Good question. The answer is no idea. If I had to guess, I would say about 4 or 5 years ago.

[Bitter]

have you changed the O2 sensor? is the coolant temp reading normally? does your car have EGR?

[speedy25]

Originally Posted by jawsofire

Good question. The answer is no idea. If I had to guess, I would say about 4 or 5 years ago.

SO you expect your car to run forever with no check engine lights while you skimp on maintenance?

Get to work!

-SP

[jawsofire]

It became my car recently. Had it for like 2 years. It belonged to my mom until she got a 9th gen corolla. So I don't know what has been done to the car until she handed me the keys.

[Suprawillis]

If your EGR system is clogged, sometimes it will throw a CEL at high speeds. You can always take to autozone and they can pull the codes for free.

[jawsofire]

I pulled the code, its ODBI. Code 25, which is a lean mixture.

[1jzdreamer]

Im assuming while cruising at high speeds, where the o2 is reading. The o2 is used for adjusting the mixture during cruising in modern cars, not really acceleration. As mentioned a sticky egr could be the culprit, an exhaust leak ahead of the cat could cause it, bad o2, or fuel starvation. The last one is unlikely unless you have very dirty fuel. I cut apart a 10 year old fuel filter and it was still pretty clean.

[jawsofire]

I have the 1.6 and from what I remember I don't have an EGR. So I'm guessing its my O2 sensor.