I've had this problem for like the last 6 months or so, although it got much worse during the last few weeks. Basically like 50% of the time when I drive the "check engine" light goes on and the car is kinda rough at idle. I took it to have some diagnostics done and they said I needed new spark wires + distributor cap. I've replaced those, and also got new sparks. Still the same. When you put your hand to feel the gas coming out of the muffler, you can feel it coming out in bursts. Also, when the check engine light goes on, the car loses some power. I am going to have it re-diagnosed tomorrow for free again and if nothing shows up do some compression tests because my friend suggested it might be the valves. Any ideas? I hope I am not f**ked .

 

is your car an automatic? the only time my light came on was when i moved the thorttle position sensor back too far...loss of power when the light came on as well...sorry if that doesnt help...im no good w/ this stuff...good luck

 

You might have to replace a couple of your sensors as well because if you have been taking care of your max (oil changes, fuel system treatments)and you replaced your sparks, then the only thing left for your electronically controlled engine to go wrong is the computer and its major sensors. I highly doubt that your computer has gone bad, so the problem may just lye between your TPS (doubtful), MAF (getting warmer), or your o2 sensor (most probable). I have done some research in the past and found that most of the time with check engine lights, they are directly related to your o2 sensor because it is a cheap way for the dealer to have you bring it to them and replace a relatively cheap part and then reprogram your computer so your check engine light doesn't come on for the next 100-or-so thousand miles.

 

I thought it might be the O2 sensor too but I replaced it about 3 months ago.