A/C Problem

[lifted_up]

My A/C works and is pretty cold, but after I've been driving and come to a red light it feels like it goes out. I can be using the cruise and after (for instance) going up a slight grade and it goes into more of a coast on the other side it will go out also. Anyone have any ideas? I added a can of freon and it wouldnt take it all so I'd say it has enough.

 

[arcticjames]

you may have the system over charged(i'm a refrigeration mechanic)with vehical a/c system the charge needs to be very precise

 

[jenmarent]

A/C Not always Cooling

My A/C works and is pretty cold, but after I've been driving and come to a red light it feels like it goes out. I can be using the cruise and after (for instance) going up a slight grade and it goes into more of a coast on the other side it will go out also. Anyone have any ideas? I added a can of freon and it wouldnt take it all so I'd say it has enough.

I had the same problem with my 99 I did the same thing as you and checked the freon what I found to be the problem was the magnetic clutch field was getting weak the hotter the temp got under the hood and would not pull the drive hub in.-mad

The way I found it was I stopped on the side of the road and checked to see if the compressor was running since the drive hub wasn't engaged I took a screwdriver and tapped the drive hub with the handle it did engage, I did this for a few days and then replaced the clutch and drive hub and haven't had any problems since.

I reccomend replacing both the clutch and drive hub around $60.00 at dealer

 

[jhess]

Hi, Freon in this case 134A, has a psi/temp. relation. Too much psi in the system will cause a higher temp. When you are run down the road it is getting cold its because your engine is at a higher RPM, this is causing the comp. to pump down the psi on the evaperator coil causing lower temps. When you are at the red light you engine is at a idle, and the comp. is not turning as fast. This is letting the freon psi in the system to rise and temp is not as cool.
So, if you added more and it didn't need it you could have Compounded your problem with another. If you know someone with a set of refrigeration gauges your low side should be about 30psi @ 1800 RPM +-
Also if/do you here Clicking under the hood when driving, as if your Clutch is cycling on and off and your sure you have psi in the system. Possable your low psi cut off is bad. Food for thought. Good luck

 

[lifted_up]

THANKS!

 

[lifted_up]

Okay, I found the real problem, the A/C clutch was worn to where there was too much space between the plates and when it got hot it could not hold. My friend who owns the local diesel shop told me to take out the shim washer. I did that and it works just fine now. I will need a new clutch on it but for now I have air, and since it hit over a 100 the last three days, that is all that matters.