2 simple (hopefully) questions...

[DSchultz325e]

hi guys i found my way over here from a link on bimmerforums. guess i'll introduce myself 8) my name is david and i own a diamond black (diamantschwarz) 2dr 1985 325e. After doing a couple of major repairs I've decided to keep it, but there are 2 more lingering problems I haven't had a chance to address with the mechanics. I was hoping to fix them myself. First...my temp gauge used to be smack dab in the middle, now it's starting to tilt towards the hot end (makes its way all the way to the second line but fluctuates every couple of minutes). Could this be my thermostat becoming faulty or something different? maybe a temp sensor? anyway, problem 2: my obc used to read the ambient temp fine until a month ago. now it reads a good 20 degrees above real temp. I can't remember where but i recall something that this uses a sensor in the engine bay? TIA.

[Ryan Stewart]

does the temp of the engine fluctuate all the time or just when you are still? If it goes up when the car comes to a stop your engine fan clutch is going. If it just randomly heats up then the thermostat might be stuck closed. It it just always runs hot there could also be a water pump issue.

The ambient temp sensor is in the brake duct on that plastic lower valance on the drivers side. Make sure its clipped in solid so that it only gets air from the brake duct.