1999 SL500 AC has been going off for hours at a time. Bought one of the recharge canisters with the gage on it, I pluged it in and needle went to the red, if it is over filled it has been that way for 12 years. Thought I would let some refrigerant out and a lot of yellow oil shot out, What do I do now.

 

if you were low on freon you should see bubbles in sight glass. the large line coming out of compressor should be cold as it goes through the firewall. make sure the compressor clutch is in-gauging. there is mineral oil in the system. climate control module, expansion valve?

 

Got the gauge in the green, compressor wont engage.

 

loose wire, bad clutch, climate control module?

 

Can't find a site glass, where is the climate control module, expansion valve?

 

the climate control module is just above the radio, the sight glass should be behind the left headlight mounted on the flat spot on the fender well. the large line coming off the compressor goes into the expansion valve at the firewall. must get the compressor clutch to engage before doing anything else.

 

Could be a loose connection, compressor hard to get too. Where is the electrical plug to the compressor. Can you get to it without getting under the car? If I have to get a new compressor, how do you pull a vacuum?