I'm having a problem with my 94 impreza. It has poor acceleration and hesitates, I found when I pulled the plugs that the two on the right side (from drivers seat) are full of carbon and the left side is perfectly clean. I replaced the plugs recently and the right side fouled out in a day. I bought new spark plug wires and that didn't help. What is wrong with my Impreza??????

 

Make sure you trace your spark all the way back. Your coil might be bad on one side, or your ignition might be malfunctioning. First step is to check the coil. If that checks out then you need a Subaru diagnostic computer (Dealerships, specialty Subaru repair shops have these) to check your ignition output.

 

Actually, just to let everyone know who might have this problem, it was the timing. I recently purchased the car, and it turns out when he had the water pump replaced, the mechanic dropped some bearings and one fell into the timing belt and jumped the timing, thats why my plugs were fouled. Its now fixed and runs like a champ.

 

Yep, that'll do it. That means your compression was off too.