I recently bought a 2004 focus 1.8 ghia. It has a misfire on cylinder 1. I knew about that when I bought it, code was giving a fuel injector problem.

I've changed the injectors, and it made no difference except now I'm just getting a 301 error. Changed the plugs, leads and coil. Still no change. My next step (when I get time) is to run a compression test. But...

The temperature gauge is acting strange. It takes quite a while to reach normal operating temperature then when it does, if I sit in idle, the temperature gauge rapidly drops down to about the quarter mark but picks back up to the halfway on increasing revs. Any ideas?