When I start my car it runs great...for about 30 seconds. Then it runs on 7 cylinders. I changed my engine harness because it was decomposed. I thought this was my main culprit. After changing it out, it still misfires. I started pulling spark plug wires until I got to #1. That is the problem. I switch the plug with #2 to see if it will change. #1 still misfires. I assume it's the wire, so I put a spark plug on it and it throws a nice blue spark about an inch! I checked the distributor cap, there appears to be snail trail on it. I clean it all up and lightly sand the brass on cap and rotor. It still misfires. Could it be a valve? I assume they are hydraulic. Why does it run good at any temperature for about 30-60 seconds and then misfire?
I would appreciate any help.