Hello, I have a 2001 Ford Mustang V6. After getting a diagnostic test, I was told that I had misfire on cylinder 3. I changed the spark plug, the problem persisted so I changed the ignition coil. The problem still remains. The wires are good, what/where do you suggest I look next?
First, check the compression. Then the plugs, not just one. The wires need to be ohmed out, not just looked at as they could be broken internally.
The injector need to be checked along with the wiring. As lastly, look for vacuum leaks as that may also be the issue with the high idle. If not, the idle control valve may be bad