trackjunkie

Hey all, I'm thinking of getting a '94 E320 w/ 79k on it. The only thing holding me back is that the car runs rather hot. The temp needle reaches just shy of the 120 mark when just sitting in traffic. I took only a quick glance under the hood to investigate. Here's what I found: there is quite a bit of pressure in the overflow tank, the cooling fans don't have much of an effect on temp and the biggest tell tale for me is that of the three hoses going into the thermostat housing, only one has pressure. The other 2 are completely soft. Does this sound like a stuck thermostat to you guys? Hopefully it won't be too big of an issue. Thanks in advance...
-Tom
'95 M3 (track car/daily)
'94 Miata (track rat)

vinamg

Check the following:

1. Engine fan clutch. This is the big one located in front of the engine.

While the car is running hot (raised hood) shut it off and quickly check fan, if it doesn't stop spinning within a few revolutions (free wheels) you need to replace it.

2. Make sure the thermostat is installed. If it was removed it can cause overheating problems

3. Check if the electric fans are working when you turn on AC.

4. Double check blue (two pole) coolant sensor next to thermostat. It should activate electric fans when disconnected (running engine).

rallyeslide

If there is no thermostat, how would that cause it to overheat?
It would definitly take forever to warm up, and might run too cold though....

vinamg

It's a bypass design. If you remove the thermostat only half of the coolant will go to the radiator.