Wasn't sure how else to title this but I'd like your opinions on something. I just took a trip last week from Pittsburgh to Williamsburg, VA (close to a 7 hour trip). On my way down there it was a very hot day and for the 1st half of the trip everything was fine. Truck was running well, ac working well, etc. Well, when I hit I95 the trouble started. For whatever reason, I was running into traffic jam after traffic jam for no reason on that highway! Well, after about the 5th jam, my AC started blowing hot air. I checked both sides (low side and high side) with my gauges and they read normal. Well, eventually after the truck sat for a little bit, the cold air returned. The rest of the trip down it was fine and it's been fine ever since. I didn't run into anymore traffic jams after that thankfully. It was about 95 that day with the sun beating down. Anyway, I know my system is old and is going to need replaced soon. Could that have just been an old compressor acting up in the extreme heat and conditions? Did it maybe just shut itself off due to the conditions and how old it is? Or, is there something else that could've caused that? Engine never overheated or even got excessively hot through all of that. AC just blew hot air right after the stress of the heat and traffic jams. Thanks for any advice on this.

 

My guess the evaporator froze back to the expansion valve, shutting down the flow of refrigerant. Defrosted during sit time allowing system to function again.