I just picked up a 92 325is for a great price. This is my first BMW, and I had some questions about mechanical oddities.
First, The OBC says to check coolant level, when I did it was indeed full. After some reading I suspect the float is gummed up or the switch is bad... easy enough fix.
Second The Temp gauge is all over the place. When on the highway, the gauge is steady at about the 10:30 position hovering right around the first line. Normal town driving the guage will come up to half, sometimes a little past half. Does this sound normal? I plan on doing the fan mod and cleaning up the float this weekend along with a new water pump.
Third, after driving with lights on, the OBC says Tail Light Failure. Reading tells me this is probably incorrect bulbs.
Last and most worrysome to me is a misfire under load, usually under 2500RPM. I replaced the plugs yesterday, but the miss is still there... seems to miss only after 10 minutes of driving. Engine cold, it runs fine. I am leaning toward coil packs, but have no way to verify which one is bad. Can someone help me out with the diagnostic? I doubt it's O2 sensor, but it probably needs changed anyhow. Is the BMW O2 sensor narrow range or wide range? 1, 3, or 4 wire?
And I would also like to check the ECM codes. What's the procedure for a 92? Build date is 2/92.
I do have a Bentley's manual on order.