300D 2.5 AC not working

Take it to a shop and have them put some UV-sensitive dye put into the system along with some more refrigerant. When the A/C stops working again, bring it back and have them use a black light to track down the source of the leak.

Geoff

Geoff,

I did that. And they claim it was the low side > snipped-for-privacy@gmail.com writes:

What is the pressure when engine is not running? It need to be at least 50 or 60 PSI before the compressor kick on... and then it will start to take in refrigerant.

If pressure is low, then hook it up and shake the can to force more pressure until the compressor kick in and start to take more.

When compressor is on and running... about 32PSI. When the compressor is not running, it is about 90PSI.

What is your current PSI? with engine off? engine on?

It's entirely possible, although I don't see why that would prevent the clutch from engaging. I once had a situatioan with my 300CD in which I could tell the clutch was engaging (I could feel the slight loss of power when it kicked in), but the A/C still blew warm because of depleted refrigerant. Topping off the R12 worked for a couple of months, and then the problem started again.

I'm at a loss, since your situation is beyond my experience. At this point I'll have to defer to somebody else with more in-depth knowledge of air conditiong.

Geoff

It is possible he has compressor problem.

Your compressor is definitely not running. By the drier... driver side behind the headlight... make sure the wires are all connected... if yes, then I'd like you to bypass them... connect both wires together to force your compressor to run.

In any case, if you dunk your R134a can into hot water, it will fill your system to higher pressure... You must have low refrigerant in the current can that it won't fill any further.

Let me clarify... connect the pair together at each sensor with a wire or tape.

Tiger's right. If you don't have enough pressure in your system because of low refrigerant you need to by-pass the low-pressure switch located near the drier mount. Again, this is located behind the passenger's side headlight assembly. You will find a plug with two wires going to the low pressure switch. Unplug the connector and insert a jumper wire between the two female terminals in the plug, not the switch on the drier mount. This should cause your compressor clutch to engage with your temperature switch turned to max cold on your center counsel and the center button depressed. Make sure your fan switch to the right of your five push buttons is set to either automatic or max. One other note, make sure your engine is running when you do this procedure.

If your compressor comes on simply set up your gauges and load up your refrigerant on the low pressure side to somewhere between 35 and 40 psi. I like to look at the sight gauge located down near the drier and continue putting in refrigerant until the bubbles completely disappear. This is usually the maximum you can achieve without overloading the compressor. Once you've achieved this your system should blow cold, especially if you are still using the old R-12 refrigerant. If you're using the newer R134a it will cool good but, IMO, not as good as the R-12.

If your compressor doesn't come on when you insert the jumper wire in the low-pressure switch you have other problems. If that's the case reply and we'll take it from there.