Engine Performance problem
2003 Ford Windstar 6 cyl Front Wheel Drive Automatic 77000 miles
Number 2 cylinder mis-fires per Autozone engine analyzer. I repalced the plugs ( Number 2 plug was black ), and plug wires. No change. When you attempt to accellerate, mis-fire is more noticeable, and enginer knocks and hesitates. Let off the gas pedal, and it get's smoother. Also put 4 cans of STP gas treatment in the gas tank to eliminate any potentil water in the gas. Only other options I can think of our 1. Bad coil pack, and 2. Bad fuel injector. Your opinion?
First, check and make sure the crank sensor is clean and tight. The knocking noise makes me think timing. Next, are you getting spark to the missing cylender? If so, have you checked (using a noid light) to see if the injector is getting power?