1999 2500 Air goes Cold To Hot

[Hardwood Goat]

Today I noticed that driving on the highway the air conditioning would go from cold to normal. Just has surges of luke warm/vent temp air. Can I recharge myself? It has the capability of working just fine. Whats the fix?

[MT-2500]

Originally Posted by Hardwood Goat

Today I noticed that driving on the highway the air conditioning would go from cold to normal. Just has surges of luke warm/vent temp air. Can I recharge myself? It has the capability of working just fine. Whats the fix?

Give us your low and high side pressure reading with compressor running at adle and at 2K rpm.

[DFBonnett]

Originally Posted by Hardwood Goat

Today I noticed that driving on the highway the air conditioning would go from cold to normal.

Does this occur when accelerating or going up a hill or is it also evident when maintaining a constant speed on flat terrain?

[Hardwood Goat]

It happens on flat highway too. But when its on max its not as bad.

Not every forum user has access to a set of shop manuals. Auto Zone web site doesnt even tell you wich is the hi side.

[MT-2500]

If you are going to DIY it you need to get the proper tools.
You can not check or test or charge it without them.

http://www.ackits.com/merchant.mvc?S...erantGaugeSets

If you do not find the info on AZ web site check with you public libary for car repair info or http://www.alldata.com/products/diy/index.html

[MT-2500]

Anddo not even think about one of the death kits.

Wal Mart DEATH KITS

You cannot properly and safely recharge an air condition system with them.

The one side stop and go gauge does not tell you what your system is doing or is over charged or undercharged.
A overcharged or malfunction air condition system can reach over 500 lbs of pressure.
Enough to blow up that can or system and freeze you at first and the burn you or blind you and if any propane /butane in there blow and light you up.

The stop leak crap and who knows what kind of oil in the kits there will stop your system for sure.
Just like pouring super glue in it.
And some kits even contain freon with a butane mixer.
Good for a big blast.

If you are going to do it do it right and safe.
Here is what you need to start with.
http://www.ackits.com/merchant.mvc?S...erantGaugeSets

In the older days you could just throw in a can and go.
But over the years just adding freon is getting harder to do.
Newer systems have to have the correct amount of freon down to the ounces.
Most will need pumped down and vacuumed down and the right and amount of oil and a set amount freon charge installed to get the air to cool right and the system to last.
If an air condition is low there is usually a leak that needs fixed and also a lose of lubricating oil from system.
Also air and moisture enters a low system
If you are going to try to do it get the proper type air condition gauge set with the low and high side gauges.
Hook up the gauges and get a reading with compressor running at idle and at 2000 rpm on the high and low side.
Post back pressure reading and we can help you.
MT