benzmac
i read with interest your reply to nick jamal
about an ac problem with his 86 300 e , and i have some follow up questions.the ac on my 87 300e works great around town,really cold air.it seems like when it goes on the highway
after a while the fan is still going but nothing is coming out of the vents.when you turn the fan on high you can hear it going as loud as it always is but barely any air is coming out.what little air does come out
still seems to be cool,but it gradually diminishes to nothing.if i turn the ac off
and turn it back on after 15 or so minutes
while still traveling all the while it will
be fine for a few minutes and then the air flow goes down again?going around town at 35 to 50 mph we have no problem.i suspect possibly this sensor you refer to that is on the back of the compressor that goes bad above a certain rpm.do you think that might be the problem? if so, is this sensor available without having to buy the whole compressor?and can you tell me where i might buy it?or could there be something else going on?thanks for your help
greg stein

I believe that what is happening on yours is that the evaporator is being covered with ice! I have seen this before when the drains are blocked or when the evap temp sensor is faulty and not cycling the compressor. If the sensor on the rear of the compressor fails, it will not come back on until you turn the key off and back on again.

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

benzmac
>thank you for your imput on my ac problem. i did have a sense that
>something was freezing.about the drains you mention that might be blocked,
>can you tell me where they are?and also where is the evap temp sensor.
>thanks.
>greg stein

The drain tubes are located under the car above the transmission. The evap temp sensor is located in the heater box beside the drivers right foot.

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