A/C not working?

CHTWOOFUS12

MEMBER
2011 SCION XB
98,000 MILES

A/C turns warm when slowed in traffic or at a stop, but only sometimes. Sometimes it just stays cold. It has no constant pattern. When it's warm out it tends to do it more often. A/C has been checked and checked. Charge is good and everything is working. Replaced thermostat which did nothing. It's so frustrating. When it blows warm if you start driving it turns cold again. Sometimes if you hold RPM's at 2 while stopped for 3 to 4 minutes it cools back off, but sometimes it doesn't. Checked all vents and filters as well. Please tells me how to fix problem.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

We need to start with checking the pressures. More then likely you are low on freon. I understand you said the charge is correct but if we have not checked the high and low side pressures with a gauge set then we can't be sure.

Here are some guides that will help with this:

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

Once we know what the pressures are, we can view this chart below to find out possible causes. Let us know what you find with this and we can go from there.

Thanks

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