I want to confirm if mine did.

I was on the way to having the Evo II wheels installed when I got stuck in a 45 minute bumper to bumper traffic jam. (It was a pretty warm day, say around 30C/86F.) 30 minutes into the endless crawl, I feel the car's idle get a bit lumpy and the tach begins to dip to a sub 500 rpm idle. The engine temp reads 40C. I turn off the a/c and open the windows. 10 minutes later the car starts to shudder a bit and I really begin to get worried. Engine temps read somewhere around 60C now. I try giving it a bit of gas and it feels like it's in limp mode. Sluggish. And the engine sounds like it's gasping for air. I wasn't sure if it was overheating because the temp guage was saying otherwise.

Another 5 minutes and I get to the tire shop. Where I have to negotiate a bit of an incline (6 feet 10 degrees or so). Car dies, idiot lights come on.

I get out, pop the hood and let the car cool. The engine seemed hot but no smoke or steam.

After the wheels were installed (hour and a half or so) I took out the radiator cap. Water level was right there at max. Drove the car home without incident. I left the car idling for some time (another 20 to 30 minutes or so) and after the auxiliary fan kicked in the temp guage was dropping (from around 60) so I gave up.

Tried it the past couple of days and it seemed fine. Couldn't replicate it. Maybe it was a fluke.

Does the above sound like symptoms of a car overheating? Haven't had a car overheat on me in the last ten years or so but the two or three times it did happen, engine shut itself of as well. They were both stick shifts though so the power loss was not apparent to me then.

For sure, my temp guage's busted at the very least...

Any ideas?

The car's definitely going into the shop this weekend! And I guess I'm ordering the oil and tranny cooler sooner than I planned!

__________________
Rainmaker
93 500E, 43k mi, Pics of upgrade parts
Evo II Wheels on Dunlop FM901 235/45x17s
94 Facelift
RennTech CF Airbox
RennTech ASR Defeat
RennTech Chip
1st Gear Start
97 Range Rover 4.6 HSE Vitesse, Yellow, "Tonka" (sold)

Do you recall "hearing" or "feeling" you aux fan kick in the traffic crawl?

If not, aux fan operation(s) should be checked (a short affecting aux fans? or fuse?).

Proper aux fan operation posts seem to crop up when the summer temps heat up.

There's a few tests you may wish to do yourself to satify your own curiosity (do search) ie a/c on= aux s/b on low speed, etc. etc.


fyi- I drove in 80-85 degree 30 minute stop and go Los Angeles traffic- climate control set to a/c-68 degrees, (aux fans inoperable) and my temp did not go above 100. After I got back to SF, I asked SF MBZ to check system and they found a bad relay and replaced it under Starmark warranty.

Also fyi- , it was about 90 degrees in the Bay Area this weekend. I drove with a/c both in stop and go traffic and at 85mph freeway cruising....and temp did not go significantly above 100.

re: trans and oil cooler, I recall a post where one person's thought was that it did not help keep engine temps down with regular duty use (in other words, effective for mountain driving and towing use). In either case, let us know if it does significantly lower temps. I believe that Scott Shell has the Renn version installed and wonder if he's seen any significant drops?

It may be of interest to you to try Italian Benz's home made relay to kick aux fans in between 80-90 (its cheap and easy to install from what I understand).

Other things come to mind that may help:
water wetter, lighter oil viscosity, rad/ engine flush, fresh MB coolant mix, adding cooling vents replacing headlight wiper panel.

Good Luck and let us know how it turns out.
-fad

fad,

I was too busy trying to figure out why the idle was lumpy all of a sudden that I forgot to notice whether the aux fans came on while I was stuck in traffic.

I'm having the temp gauge, temp sensor, fuses, and whatnot checked this weekend. I'm also replacing the expansion tank even if for no other reason than aesthetics (it's yellowed already). I'm researching putting in an electric fan in place of the clutch fan as well.

I already got myself a couple of bottles of Water Wetter but that goes in after the everything else gets checked, the radiator flushed, and I pour in the coolant/water myself.

The person who *thought* that the oil and transmission cooler does not significantly aid in normal driving was just expressing an opinion and had no facts nor experience with either the oil or tranny cooler. I figure if it cools the oil, it cools the engine. And it's "summer" here most of the year anyway...

Thanks! Will report back on this one after the visit to the shop....

__________________
Rainmaker
93 500E, 43k mi, Pics of upgrade parts
Evo II Wheels on Dunlop FM901 235/45x17s
94 Facelift
RennTech CF Airbox
RennTech ASR Defeat
RennTech Chip
1st Gear Start
97 Range Rover 4.6 HSE Vitesse, Yellow, "Tonka" (sold)

My basically stock 500E temps run between 80-110 celsius here in New England during normal driving which is anywhere between 70-100 mph about 3-4 times a week. Of course on a hot day and a few minutes of 120+ driving will cause the temps to rise higher but the fan will kick it back down to the safe zone in no time. Sometimes in traffic and the heat the car will seem to skip for a fraction of a second but holds the 500rpm idle but I figure I need a fresh tune-up at 125,000 miles. I did put Redline Water Wetter in the new coolant I have but can't really tell if it makes a huge difference...I've only had the car since feb. 2001. I have a feeling they were built to withstand high engine temps as well as high sustained speeds. I might go with Guidos new invention if I were you...a cheap upgrade that sounds like it'll do the job of cooling quicker.

Jimmy
1992 500E Malacit Green

Well rain. Jims right. Its funny jim im on boston on the east coast visiting from southern calif its gorgeous outhere.

Rain for starters. I think no mb shuld be running at 60C. The darn thing would still be in open loop. You have
a bad temp sensor for the guage. The guages dont really go bad on these, there pretty much solid state. In all my yrs as a MB tech i might of replaced say 2 gauges,I highly doubt yours is defective. Im leaning towards that black one pole piece sensor. It controls them temp of the guage.
It you do mechaincal work theres an easy way to test it.
Thats one problem.
What farruk i think mentioned happens the aux fan relax goes bad. But you can it.
1. Removed that plastic panel you see in front of the aircleaner just pulls off. You'll see a blue 2 pole piece sensor with a wire connector attached to it. Press in the tabs and pull it off. Jump a wire or paper clip from end of the conenctor to the other igntion on, if you fans come on its not the relay, its the blue sensor be sure to chekc all your fuses like farukk mention. 2. If the fan comes on drive it around and see with the heater on if temp stil climbs, if so you need to put a new thermostat they go alot on those 119 engines. Also when after your drive when it starts getting warm. Pull over turn engine off. Feel the radiator in the middle on the engine side can get your hands in there its tight but yu can. If you have cold spots in certain sections you need that T-stat,and you need my cooling mod harness he he<. It cheap insurance alot of 500E guts are very happy

Good luck guido.

Bingo!

Aux fan's on 24/7. Sure glad it wasn't anything more than that. The temp guage is still off and that still has to be fixed. In the meantime, I'm back in business! Thanks, Guido!

Just a couple of observations...

-the wires going into the connector attached to the sensor was frayed. I guess that's the culprit. The poles are jumped in the meantime pending the arrival of the parts I need.

- with the wire connector unplugged, the auxiliary fans are on as well. With the wire connector installed, fans don't work.

- I opened the fusebox to check the fuses. All the fuses were in great condition but apparently, for the 500Es the fuse for the auxiliary fan, the heated seat and one other thing (I forgot) is outside the fusebox. Anyone know where it is?

Also, where is this "black one pole piece sensor...that controls the temp of the guage" located? Is it the one right beside the blue sensor?

Thanks!

__________________
Rainmaker
93 500E, 43k mi, Pics of upgrade parts
Evo II Wheels on Dunlop FM901 235/45x17s
94 Facelift
RennTech CF Airbox
RennTech ASR Defeat
RennTech Chip
1st Gear Start
97 Range Rover 4.6 HSE Vitesse, Yellow, "Tonka" (sold)

Hi randy. You need a new engine wire harness. Mercedes benz goodwilled the factory hanrnesses up to 100k they new it was a problem. That what was going on with mine.

If you disconnect, the harness. After a while fan will not come on. In order to keep the fan running 24/7 you need to jump the hanress like I mention.

Randy you really shoould get my piggyback harness it works great! Let me know. yes the black one pole sensor is for the guage.



Guido out.