I was stuck in traffic for around 10 minutes the other day, and I noticed my temp gauge started to rise rather quickly. I thought that the fan would turn on but it did not. I was on a hill and had nowhere to go and couldn't shut off my engine. The temp went up to the red mark and some steam started out from under the hood. I finally got to where I could get the car moving about thirty seconds later and the temp dropped. Is it possible that I damaged something and what should I look for to be faulty- cap, thermostat etc. It has never gotten this hot since I've owned it and I'm relly worried. Also, there is a click in the engine when idling. Is it possible that I have a bad water pump?

The fan(s) should have come on and cooled down the engine. You probably did not hurt anything. You need to have the fan(s) checked by a tech for proper operation.
Do you have a 2.3 or 2.6?

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

I have a 2.3 liter. also, there is a click or knock at startup and idle that sounds like it's coming from the lower part of the engine. It goes away with higher engine speeds. Is this possibly a timing chain problem? One last question..is there a relay for the wiper motor and if so, where is it located. My wiper doesn't work and I've replaced the fuse...I hate to replace the motor. HELP!

I think it is in the fuse box, the big
relay with SAE on it. good luck.

About the tapping sound. We have had many 190Es come in with failing oil pumps. Watch your oil pressure gauge, make sure it is at 1.5 bar at normal operating temp idle, and rises to 3 bar upon acceleration. As far as the overheating goes, you'd better have the aux fan checked out, it may very well be locked up. If the problem persists after the fan is R&R'd, next try replacing the thermostat. However, usually when thermostats are near the end of their life span, they will tend to stick and cause the engine temp to rise to overheating then drop back down to normal. You might also want to replace the radiator pressure cap at this time. Next two items would be the water pump and radiator. I just put a radiator in a 450SLC that came in with the same type of symptoms as your car has, and that did the trick. But have the aux fan checked first and foremost!



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Rgds,
Aaron Greenberg
MB technician
'67 250SE Cabriolet
'77 450SL
'79 6.9
'79 6.9
'80 300SD
'81 240D
'85 380SE
'89 420SEL
'93 300E 2.8

My oil gauge reads 3 bar at idle. only rarely does it drop down to two. Is this the sign of a faulty pump? Thanks Aaron for your other advice.

Your oil pressure gauge should only read 3 bar when the engine is cold and idling (i.e. after cold startup). Once the engine reaches 80*c, the needle should drop to 1.5 bar at idle and rise immediately upon acceleration. I'd have that looked at as well. Could just be a faulty sending unit.

I also have an 86 16 valve that did the same overheating thing. It overheated and blew a gash in the plastic part of the radiator. It is all fixed now. The culprit was a bad temp sensor on the water pump. It has a red base with a wire attached. This is the temp switch that turns on the engine fan clutch at 100 degrees C. I replaced this 15 dollar switch and low and behold, the fan comes on now at 100`C and shuts off the fan at about 80`C. Try the switch first.

I have another question, is there a switch that turns on the fan clutch at 80`C? I know from owning VW's in the past that by replacing the temp switch you start the cooling process earlier. Will this make the M-Benz motor work a little more efficiently?
Thanks, Joe