this is a crazy one.i have a 2005 honda civic my a/c has a mind of its own.it work on and off.it has no leaks and refigerant is full.what ive noticed is that during hotter days like lets say 75 degrees and over there is no a/c it turns on but blows hot air all the way.but when the temp is cooler it works awesome super cold no problem.just wanted to know if there is an easy fix or has anyone else had this issue..all advice and help will be greatly appreciated.

 

I have the same issue. When it does work in the warm weather it's for the first 5 minutes and then it quits. If i leave it off while driving, sometimes it comes back on for a short while. Maybe it really is low on refrigerant.

 

You say your system is full, what are your pressures? That's the only way to truly tell your system is full. If it is, it sounds like a compressor clutch/field coil problem. When its acting up check the resistance of the field coil. Should be somewhere between 3-6 ohms (not very much). If it's OL, some crazy high number, or bounces all over the place you need to replace it. Also make sure the clutch clearance is in spec. I think the specs are between 0.015-0.030 give or take 0.005.

 

Go to the carwash and spray the whole front end of your car down. You want to get your radiator and everything in front of it clean.

After you do this, go pick up one of those cheapo a/c charge hoses from autozone that has a gauge on it; it shouldn't cost more than a couple bucks. Dig an empty R134a can out of autozone's trash can and stick it on the end of your new charge hose so that the pressurized refrigerant doesn't blow out of the end of your hose. With the a/c on and car running, you should have around 30-35psi. If pressure is lower than that, you need to add a bit of refrigerant and I would throw a dye in it because you're probably leaking. If pressure is higher than that, then I would run down to an auto shop to have them vacuum out and refill your system.

If your pressure is normal, then look at your compressor. Is your clutch kicking on and off or turn on and stay on continuously? Are both of your fans on the entire time the a/c is on?