twrv

2001 Cherokee Sport with 110,000 miles. For about three years now, the A/C has been acting up. First, it will blow cold air for about 10-20 minutes, then it starts blowing hot. Sometimes, I can shut off, wait a few minutes and it will start blowing cold again.

I've had it checked by 3 mechanics who can't seem to find a problem. I've had a new radiator put in and had the refrigerant checked and that hasn't fixed it. Does anyone have any ideas?

freegdr

Is compressor staying engaged when it starts getting warm ?

twrv

I'm not sure. Mechanics say everything is working as it should. How can I verify that?

freegdr

Look at it would be a good place to start .

tjwalker

Are your mechanics AC specialists?

Air conditioning is a specialty. The same guys that replace your starter and brakes might not be the guys to troubleshoot a subtle AC issue, even though they might have the capability to recharge your system and check for leaks.

I would certainly think that a good AC tech would be able to get under this problem if you left the vehicle with them and they could replicate it.......

mikerosa

The clutch for the a/c compressor has to be disengaging if you find no other issues.

You might look to check your fan. When the fan shuts off, there are sensors to **** the clutch down on your A/C.

One such instance of this, I wired my electric fan constant on a Chevy and never looked back.

If you don't have an electric fan then this won't work. I would then look at the fan clutch to see that it's still turning a lot of wind to the radiator.

investinwaffles

My e-fan does not work, but the AC will stay icy cold all day long.

It could be a heater blend door issue?

cherokee001

i have the same problem... Winter is around the corner so i'm not worried about this till next summer

CCKen

First, go here and scroll down to post #42.

https://www.cherokeeforum.com/f2/gre...e-6558/index3/

Read about the 2K/2K1 AC system.

Then describe what is happening in great detail, if you can.

mikerosa

I am 99% certain your fan must work in order to cool your condenser. If it doesn't work, your compressor builds up too much pressure and usually blows your seals.

One other thing I forgot to make mention. Sometimes when a compressor blows up, it sends garbage thru the system. When you replace the compressor the system is evacuated. But the condenser can hold some stuff like burnt plastic/ rubber. It comes loose and eventually ends up in the filter or what's called the orvice tube of the dryer and clogs the system. When the system clogs, the freon cannot circulate and won't cool.

You can have an old faulty portion of burnt debry or it might be breaking down now.

Chris Buslovich

This started happening to me today. Was it the e fan?

netvvork

I have the same issue. Mechanics tried all sorts of things and everything checks out.

4x4jeepmanthing

congratulations, not, you probably have a leak. good news is it is you can identify it! use some uv freon from the parts store. Charge the system to the gauge reading in the green. you will see UV dye with a UV light where ever its leaking, and it will leak for sure. Youll need a shop to evacuate the system once the leak is found. fix and replace the item. if this has been done properly and you dont see dye, you leak may be in the fire wall, it happens.

your mechanic needs to be replaced its a closed system, if dye is used and something escapes you will know. tell tale sign of a leak is cold air then becoming warm. this can be gradual or all at once. only other senario is a real wonky blend door/ thermostat issue which has a lot of variables that i just dont think youll see.


look for dye gents, itll scream leak.

Troy Emerson

I had a similar problem with my 01. The solution for me was to remove the clutch/pulley from the a/c compressor(after releasing the serpentine belt). On the shaft if memory serves there were like 3 copper washers. The advice I got was, if there are 3 washers remove 2, if there are 1 or 2, just remove them altogether. Reassemble pulley and belt and try it out. The point was, the washers had something to do with the magnetic clutch engaging. Fixed my problem 100%! I’ll try to fine the link to the fix if I can. Hope this helps.

found it!
askingxforxit’s reply,

https://www.cherokeeforum.com/f2/ac-...rm-air-226029/

Silver01Bullet

I had been fighting the same thing for the last 2 summers, but we also found a leak around the low side shrader valve and the hose crimp to it. Replaced the lines and accumulator to get rid of the leaks, recharged, and it still cycled from cold to warm after about 15 minutes. The electric fan on mine has never seemed to work properly. After all of the time that has been spent troubleshooting this, I decided to go ahead and pull the clutch and look. There was only 1 shim there, but I removed it, reinstalled the clutch, and fired it up. The electric fan came on immediately, and the clutch now stays engaged. No more cold-warm cycling, the temp in the vents on max air gets to, and stays at 42-45 degrees. Yesterday was a 107 heat index day, and it worked perfectly.
Its a 10 minute job to give it a try, but in my case I had to first know that the system was leak free.