Something weird, can u all help?
 

Ok, 2 things. I've noticed that after a 10-15 min run on the highway my "CHECK ENGINE" light turns on. What can this be? Some one told me the O2 censor? Another thing, when i'm on the highway hitting about 40mph and up, my engine will all of a sudden rev a bit up? The rpm's will all of a sudden go a slight up. I really don't know how to explain it. It happens when i'm going on the highway ramps too. It'll sound like if i'm punching the gas for a second or two, then smooth out, then all of a sudden again, then smooth out. It'll do this about 1-3 times. What might this be? Thanx for any info!

I have the same problem on my car. IF you have replaced the O2 senser, then you might want to take your car to a shop that can read your computer. I am not talking about just reading the fault code, but tell you what you car is doing. My next guess would be the EGR valve or the sensor. That is why you might want to take it somewhere to see what is faulting what. I am not sure what EGR really does, but it might have something to do whith the choke. If that is the case it might explain the way the car reves.

To me, at least, it sounds like a bad Throttle posistion sensor. I dont think the ecm is getting the proper signal from the sensor, or the sensor is sticking, and that might explain the revving and the ENGINE light. BTW, you should learn how to read the computer codes yourself, all i use is a paperclip to do it. But if you dont feel like doing that, autozone will help you read the computer and then they'll tell you whats wrong with the car, and then you can replace the faulty part. If i had a mechanic do my computer diagnostics for everytime something went wrong i would have spent enough money to bankrupt most third world countries. Thats just my opinion though