My son could not get the key out of the ignition of his '91 740 (non-turbo) and it was running, so he pulled the spark plug wires, one by one, until it stalled out. Now it will start, but is missing so badly that it really cannot be driven (no power, backfires, etc). I am 99% sure that the wires were put back in the proper order, but cannot be sure since I don't have a wiring-order diagram. I have tried various combinations and the one I currently have, which is the one he thought it was (no, he didn't number them before pulling them!), appears to be the only one that will allow the car to start. I have replaced all the wires, and I have pulled the plugs to make sure they aren't fouled.

Two questions:

1. Does anyone know where i can find a wiring order diagram for the 1991 740?

2. Can anyone think of a reason why pulling the wires while the engine is running would cause it to have such a misfiring problem when the wires are put back on?

Any recommendations would be welcomed! Thanks!

Mark