I bought a 2003 mini Cooper last year from a private sale. Drove it for a couple months with no issues. Parked it for the winter. Went to get it ready in April to drive again and it flooded which happened from the drain tube on sunroof coming disconnected. I took everything out of car, carpet and seats. Dried everything and started it up. Everything went crazy. Dash lights came on, car wouldn't shut off with key out of ignition, tack and speedometer wouldn't work, stall car to turn off car and dash remains lit, ECT training battery. I did research and found several people with same issues. I found the connector in drivers side floor X15 I believe they call it not sure if that is right but anyways wire were all corroded and a lot tell out of connector. I can not find a wire color code chart as there is like 40 wires. I can not tell a couple wires apart from one another as they are same size and color. Long story short I got all wires hooked back together and all electrical is working great. Now I start my car take on a drive 5miles and it starts misfiring on cylinder 3. Brought it home and bought new plugs, wires, and coil. Took it around town again and its still misfiring on same cylinder....im no way a car expert so my question is could the wiring on that connector cause this, could the computer do this? I did take computer out and it did not look like any water got too it or in it. A friend did a compression test on cylinder 3 which read around 60 and others were double that. So is it engine related or just coincidence?

 

Moving this to the Stock Problems/Issues area.

60 PSI could be normal for a compact spare tire but not any type car engine. You misfire could be a burnt valve.