This is a 1989 car with 180,000 miles on it. Runs fine, but engine temp rises immediately in traffic and at stop light. Water pump and thermostat has been replaced, radiator flushed and new coolant.

The normal temp appears to be about 89 degress. It climbes to 95+ immediately when stopped.

The driver side aux fan runs fast when plugged into 12V, but the passenger side aux fan does not. Also the dirver side fan does not turn on ever, unless I am testing it.

I am not a mechanic. I'd like to know how to determin the problem. Temperature sensor, relay, do I need both aux fans working.

A new fan form MB is $340, relay $27 and sensor $35. Can you tell me how to test, where the replay and sensors are, what they look like.

The parts at this site cost less, but MB tells me not to buy anything but BM for this car. I am reluctant, but presume these parts are OK. Are they OK?

Obviously I am a novice to MB, but no idiot under the hood.

Thanks.

Dan