After a fill up today (not full) I noticed the service engine light on. I pull over soon and checked under the hood. Didn't notice any strange sound, and all the fluids looks good. Checked if the gas cap was tight and turned off and on the engine. Light is still on. The car seems to be running fine, and nothing noticeable. What might it be? Might have to take it in to the diagonstic on Monday...

 

this has happened to me, u mean the 'service engine soon' light rite?

if u fixed ur gas cap, check it again and click it about 5 times. then after about 3-4 drives, if the light doesnt go off, then take it in, its a free check from the dealership.

 

I am not sure, but would the knock sensor throw a check engine light? Could be bad/low octane gas causing the motor to detonate/knock. Hard to say.

 

If you change gas or don't use a good quality gas the check engine light will sometimes go on. there is nothing to worry about though. it usually takes a day to go off.

 

I have had this problem to... a few times. The first time it happened to me, I was travelling. I brought it to a dealer and had it fixed... ended up being the oxygen sensor in the rear. About 3 months later, I am driving down the road and the light comes on again. I went back to the dealer and it was the oxygen sensor in the rear again. I asked the mechanic what i can do differently to avoid this from happening... I have never put anything but 93 octane in the tank, and cant think of anything else that might cause it. He told me that it has 2 oxygen sensors in the rear, and it was the 2nd that went out. Glad I didnt do anything. Kinda sucks that the problem has occurred twice, but at least it was covered under warranty. At least the light was solid... if it was blinking, I guess the problem would have been more severe.