'91 190e 2.6

My 2 front aux fans seem to run early and often. My Temps seem to be running normal (just above 80 on the run, closer to 100 in stop and go) but it seems my aux fans are going almost all the time - that I can tell when not at high speeds (with or without A/C). Sometimes If I come to a stop, they will not be running, but if I start the car within, say, 30 minutes, they will come on immediatetly with the temp gauge right around 80.

I have a '92 190e 2.6 and the aux fans on it do not kick on until the temp gets closer to 100 and they do not seem to run near as much.

Which is normal, and where should I look / check / change if needed to get them running properly?

Thank in advance,

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Toddro
Franklin, TN
'92 190e 2.6
'91 190e 2.6

Aux fan operation on 1988 & later 190E 2.6's should be the same!

With A/C pressure; the fans are designed to come on at 225psi of refrigent pressure.

With engine temp the fans should come on at 107C

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So if they are coming on when the temp is below 107C and the A/C is not on, what would that indicate? A faulty temp sesnor somewhere or something causing them to engage before they should?

Thanks,

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Toddro
Franklin, TN
'92 190e 2.6
'91 190e 2.6

First suspect is a bad connection at temp sensor. If the ECU sees no resistance at sensor , it defaults to run
Check wires for flaky insulation while you are there .
Common problem
Otherwise , you have a bad sensor..check temp/ohms with chart in archieves

Info

http://www.peachparts.com/shopforum/showthread.php?t=107104&highlight=temp+ohms

Thanks for the help guys. My next question would be (and I'm sorry to sound so green here) but which sensor would the fans be connected to? On the top of the engine there is the plug with the blue top near the middle, then a smaller plug a little further back, and then a larger connection at the back of the engine near the firewall.

I'll dig around at all 3 a little later when I can get my hands dirty, but i want to make sure I'm looking at the right one.

Thanks again,

__________________
Toddro
Franklin, TN
'92 190e 2.6
'91 190e 2.6