I just bought a cherry 1994 530i with 102k miles. It's running a bit rough, like a cylinder misfire at idle and low rpm acceleration. I replaced the spark plugs and added Sea Foam injector cleaner. The old plugs looked well seasoned with large white deposits and lots of dark carbon build up. The cylinders nearest the firewall had some standing oil around the spark plugs when I pulled them out.

I read that to check the engine codes, simply turn the key on (without starting) and depress the accelerator pedal 5 times within 5 seconds. I tried that several times to no avail. Can anyone tell me how to display the codes?

I was going to do a vacuum check and have been hard pressed to locate an exposed vacuum line. Does anyone know of any "easy to spot" vacuum leaks?

I read about the nikasil leakdown problems and hope the rough idle is unrelated. I haven't been able to get under the car to check the block serial number.