1- The power drain on the engine when the AC clutch engages is now definitely much more severe than when the car was new. I have heard this is possibly a sign of my compressor needing replacement. The AC clutch servo coil was replaced under warranty back in 2009, but until recently I have had no noticeable problems with the AC.
2- The AC technically still works, but it hardly produces any cool air at idle or low engine RPM. On the highway, it blows "cold" air but not to the extent I would like it to. The only way it's comfortable in the car is at about 65-70 mph with the fan on full and at Max AC.
3- While on the highway, when we run the AC continuously for periods of, say 30 minutes or more (we have to run the AC all the time to be comfortable), then the vents start making a hissing sound as if the air is being blocked. If we continue to run the AC after that, the air almost completely stops, i.E. There is no airflow at all. We then have to turn the AC off for about 10 minutes and then the airflow gradually returns. I can confirm this is due to the evaporator icing up. Last night after we turned the AC off to get our airflow back, my wife was pelted by a couple of small chunks of ice that flew out of the vent. When the car is left to sit with the engine off there is a puddle of condensed water left by the evaporator coil drain, but I can't confirm whether or not any water drains while the AC is running.
To me, symptoms 1 and 2 could be explained by a bad compressor, but what about number 3? Could I need a new evaporator as well, or could it be that my condensed water drain is partially blocked? Where would this be located and how can I check? It definitely sounds like there is a low pressure liquid refrigerant regulation problem, like too much low pressure liquid is getting into the evaporator, (because as far as I know the evaporator should not be operating at temperatures so cold as to allow icing), but how does that explain the poor performance at idle?
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Thursday, August 6th, 2015 AT 7:57 AM
