1991 190E 2.3 Climate Control
 

Brian,

This one is really for you....

We're talking hot outside, 85+

As described above, still R12 and tight and topped up. Only 70K gentle california miles-- At highway speeds, or even around town moving more than 25 MPH, climate control works perfect.

Stop and go traffic, A/C has a really tough time keeping the car cool, even with recirc and the compressor always on selected. Front fans cycle on and off just fine. Engine fan clutch by design never actuates. (110°c switch controled? No?) Temp gauge never goes over 95°c

Question, is this just typical for the model or should I be seeing better idle performance of the A/C?

Thanks,

The clutch fan on water pump pulley should have a 100c switch. If the clutch fan is not up and running before the electric fan in front of the radiator, the the clutch fan switch is likely toast. The stock cooling fans with the restrictive shroud on the front of the radiator are marginal at anything over 90f. Turn on the AC and the situation only gets worse.

On the W201's the fresh air vacuum diaphram closing the fresh air door is critical to a/c cooling. I would start with a vacuum check on the system.

How would the vacuum diaphragm be affect vehicle speed above or below 25mph?