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Q: Ac stops being cold only at idle

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When driving the ac is ice cold. But when you stop at a red light or Park the ac will blow like room temperature air?. I can hear the ac compressor kicking in but it kicks back out a few seconds later. Then once I get moving again it's nice and cold. Temperatures are rising here in Texas and this is the car my wife and kids use. Any ideas where to start?

My car has 190000 miles.
My car has an automatic transmission.

Verify if the electric cooling fans behind the radiator are coming on. You can hear them and see them if you open the hood. Any time the A/C is on, the fan should run. When you are moving down the road, the airflow over the condenser is sufficient for cooling. However, when you stop without fans, the A/C system will not operate correctly. If fans are not running, you can check fan fuses #17 & 18 and relays #28 & 30 in the underhood fuse box. To be sure your system is charged correctly and cooling as well as it should, I recommend having a certified mechanic conduct an A/C inspection to see what can be done to improve your AC performance.

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