HELP! Air conditioner not working right - Compresser stops spinning

[BluPhant]

So, we're driving out of state this coming weekend for the 4th, and my dealer has no time to see me before then... plus I doubt I have the budget. Here's my dilemma:

Air conditioning works great when the KJ is first started. Blows ice cold. Around 10 minutes in, its still blowing, but the air gets warm. Checked, and the compresser is not spinning. So my first thought was maybe theres a R134 leak somewhere, checked the pressure on the low valve and it was damn near perfect. I added a smidge, but nothing of substance - this is the kind with some kind of oil in it to fix small leaks.

No dice, same behavior now. Anyone got an easy, inexpensive solution for me to try? My wife is beside herself with frustration; I'm really hoping for a small victory over this one.

 

[tjkj2002]

Sounds like you have a low presser switch shorting out or a the evap is freezing and shutting the pump off(bad temp sensor on the evap).Guess it's time for the old stand by---------the 475 A/C system(roll your 4 windows down and drive 75mph).Been using the 275 or 475 A/C system for 18 years,works great.

 

[BluPhant]

Wellp.. read up on the low pressure switch in the FSM, and went outside with the KJ for about 20 mins. The compressor stayed on the entire time, air blew cold. Evaporator looked fine, didnt look like it was freezing up at all.. just got standard expected condensation on it; never got covered w/ frost or anything. Was cold to the touch, but not freezer-like.

It was idle for the first 15 mins, brought it to 1.5 rpm for the last 5 mins, didnt make a damned bit of difference.

Is it at all possible this could be battery related? I'm running the original battery on an '02, and I know I'm going to need to replace it sooner or later. I was trying to rack my brain to figure what could be different from having it on the road vs idle... when we drive the KJ we drive with headlights and fogs on, so there is some draw there.... I dunno, maybe I'm reaching LOL

-Blu

 

[tjkj2002]

So you took apart the whole dash,and HVAC box, to look at the evaporator? The evap is right next to the heater core in the dash.

 

[BluPhant]

Accumulator. my bad.

 

[JeepJeepster]

Could be a wee bit low on freon. Take it to a local independent shop and see if they can hook some gauges up and check the pressures. Best way to figure things out real quick like.

 

[2003KJ]

Could be a wee bit low on freon. Take it to a local independent shop and see if they can hook some gauges up and check the pressures. Best way to figure things out real quick like.

But if it were low enough to trip the low pressure cut off switch, then it wouldn't work at all vs. working for the first 10 minutes or so.

Sounds like the evap is either freezing, or the switch on the evap is bad and telling the system it's frozen when it's not like TJ said.

 

[BluPhant]

Ok, so lets presume thats right. And lets presume that the jeep dealer cant see me before the weekend. Is there anything I can change about how I use the air to ensure that it stays on? i.e. run at lower setting, etc?

Went on a 15 minute trip this AM, it stayed cold the entire time .....

 

[BluPhant]

Quick update -- Whacking the compressor with a stick makes it start. Don't ask. Anyway, given that, I believe it to be a clutch problem and am going to pursue it further when I get home (couple states away visiting family right now)

Thoughts would be appreciated.

-Blu

 

[JeepJeepster]

Quick update -- Whacking the compressor with a stick makes it start.

-Blu

haha, that always fixes everything. Could be the contacts on that solenoid for the compressor.