GS300/ Yr 2003. A/C delivers cold air but some times it will deliver warm air. When this happens I turn Off then ON the A/C button and the cold air comes back. The Freon gage pressure reads 200 psi on the high side and 40 psi on the low side.

Any idea what is causing the warm air?

Any help is greatly appreciated.

 

Yup. I had the same issue with mine. Replaced the pump and recharged the system. After all that I still had the same problem. Someone recomended the AC relay....thats all it took for me. The relay was old and the contacts couldnt hold the current it took to keep the ac clutch engaged.

 

usually it means that it's either too high or low on freon. I don't know what the high side should be (I never check it even when replacing a compressor). When you're checking the low side, is the a/c compressor on? Is your mileage dropping (indicates more cycling of the compressor)? The a/c clutch feel smooth when you turn it (car off!)? Sorry, but I don't know what the FSM has as the stated low pressure PSI for an 03

 

same thing here..... where would i find the ac relay?...under the hood where all the fuses are?...
thanks

 

it is under the hood. They called it "magnetic clutch relay" it should be right next to "heater main relay" and "cooling fan relay"
PM me with your email addy for more info.

 

Defiantly electrical. I upgraded my alt and redid my ground system and it fixed the problem.

 

Oh SNAP ! Kaiser's still in da house !

 

Still lurking. I guess old habits die hard.

 

This recent burst of 10 posts over the last week, is the first time ive been on here in months I think.

 

I have noticed my AC doing that sometimes if I have accidentally hit the "ECT" button

 

I had the same problem with my A/C. After looking closer at the wiring thats on the compressor i found that the connector that go's to the speed sensor was bad. It wasnt making a good contact. Check this first. Maybe a easy fix. It was for me.

 

i had the same problem. i messed with wire that was on the compressor and it started working. is this the speed sensor connection? i know when i moved the it, the ac clutch would ingage properly. how can i make sure this doesnt happen anymore.