I have a 2003 ford focus 2.0 with an overdrive automatic transmission. I am having a power problem, I have a CEL for engine misfire on the #4 cylinder. Pulled the wire off and there was less sign of arc on the plug than the other cylinders. Replaced the spark plug wire and test drove. It seemed to do better until I hit a descent incline and CEL came back on and lost power. I shifted out of overdrive and got the rpm's up and it got up the hill.
It sometimes stalls when sitting and running the air conditioning.
If you have ran across this problem or have any advice please share.
Thanks in advance,
Reece