Bought my 1988 RX7 from a guy in south Florida sight unseen. He mentioned a few things:

1) AC low on refrigerant. Seller said the car had been retrofit with 134A. Gave me a receipt showing about $600 worth of work to the AC system. Today I took the car to the local mechanic for a fix. The guy found no leaks and since they had a special I had it evacuated and refilled. The mechanic brought me out to explain he thought there might be a restriction on the low side. I noticed that he had used R12 (not 134A). He stated the fittings were still R12 type. Anyway, they charged me for 134A so I hope the seller was confused about the conversion or I am looking at a real problem.

2) Seller also advised on the occassional startup he would see a "puff" of white smoke and that it didn't happen often. On about a 10 starts since yesterday this puff was more like a 5 second cloud of white smoke. Two of the starts were difficult to maintain idle for about 20 seconds but no smoke. What are we looking at here?

 

do the coolant bubble test....also check for coolant collecting in the mufflers...

 

Yeah, sounds like a coolant seal man...