That R/D has a pressure relief valve on the top which can begin spewing oil and refrigerant if the A/C system pressure gets too high. Check to see that this is not occurring when the A/C is activated. Check to be sure that the auxiliary fan assembly activates when the A/C is turned on. Also the hoses going to that R/D tend to leak, particularly the short hose going to the condensor. Often this is because it is somewhat in the line of fire for road debris, however usually if the hose is the culprit you will also see oil stains on it. It looks very rusty around your R/D (just behind the driver side headlight) - I'm assuming you live in the rust belt? Anyway, I have seen R/D start to leak from rust too. One last thing - I can't remember if your R/D has a high pressure switch in it - if it does, check where the switch screws in as well as the schraeder valve below it which can be prone to leaks if the seals break down.

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