[e_flag]

Good day,,

My 1988 500SEL has a temp. reading problem.. the temperature sometimes climbs to 100 or 110 on the gauge, but using an electic temperature probe, it showed barely 80.

When i turn off the car and leave the ignition on, it suddenly drops around 5 deg. once started, it shows +5 again... a slight revving on neutral cuses the gauge to drop 5 to 8 degrees.. IS the temp sensor fried? or maybe i have overheatin problem...


Thx...

 

[Jammerkiller]

I think that if you had an overheating problem, you would suffer poor engine performance or you would hear the electric fans come on all the time. Your best bet is to replace the temp. sending unit. I think mine cost me about $35 from the dealer but you could probably get it cheaper through Mercedessource.com or azautohaus.com.

 

[e_flag]

Thx 4 the reply man.. Well, my fan is set to turn on at 87 deg..

Ther is no loss of power at all. Just a high reading, while it is still possible to touch the radiator hoses comfortably, and the engine's fan blows mild air...

 

[Jammerkiller]

e_flag - 4/3/2006 1:13 PM

Thx 4 the reply man.. Well, my fan is set to turn on at 87 deg..

Ther is no loss of power at all. Just a high reading, while it is still possible to touch the radiator hoses comfortably, and the engine's fan blows mild air...

If your hose are not too hot to touch and you mean "mild air" as in mildly hot, then I suspect the thermostat. I also had this problem before. My heater core hoses were hot to the touch but the upper radiator hose was luke-warm. I replaced the thermostat and all was good.

 

[e_flag]

The thing is , i changed the thermostat a month ago .. well mild air means yes not too hot.

Anyway ill try changing the temp. sender// Altho im not that convinced []

Cheers

 

[Teutone]

Check out MBL87560SEC's recent posting with a diagram of the cooling system with the thermostat. I learned that the 560 thermostat has a venting hole that needs to be aligned and correctly installed so it connects to a venting outlet. Could that be it?

 

[jay300se1988]

After you changed the thermostat did you properly bleed the cooling system of air?

I've known air locks to cause similar problems to the one you're experiencing.