Question1987 4-door Camry, 4 cylinder engine, automatic transmission, 276,000 miles, various seals, gaskets, and timing belt replaced 6,000 miles ago (local Toyota dealership installed, set timing to factory specs), new compressor, new receiver/drier, new coil under dash installed. Old compressor had bearing go bad. Engine burns no oil, runs great. Problem is at idle, with car in gear, engine "surges" and feels like it wants to stall. Had new A/C work done two days ago, problem was immediately evident upon picking car up from garage, mechanic said bring back in a few days and he would check it. Also, A/C is reading 35 low side and 150 high at idle (not in gear) with R-134a...mechanic said this was "perfect", but does not cool as much as previous R-12 at idle or at highway speeds...92 degrees day today and I was sweating! What should this system be reading on the gauges and what temp should be coming out the vents? What should the idle RPM's be with the A/C compressor running? Could switching to the R-134a from the R-12 be causing this rough idle in gear problem and will a simple adjustment of the idle speed take care of it? I've also noticed that the car is not as responsive under acceleration and feels like it's under a heavy load while at highway speeds with the A/C on. Is the system under-charged and will increasing the charge put more drag on the engine by increasing the high-side pressure? What are your thoughts, as it is best to know something while talking to the mechanic...otherwise, "that's the best it gets" may be the answer I'll hear...
AnswerThe pressure readings are pretty much normal, has anyone checked exactly what the vent tempereture is, it should be about 38-44 degrees, the idle speed should increase to about 1200 rpm with the a/c on. The Idle is adjustable and so is the idle-up valve.
