AC dying after 2 hours driving at 70 mph

[Black Ram Alpha]

Evaperator slow leak

My 2003 Ram quad cab has a very slow leak in the evaperator . In shop now. When the system runs low on free-on the computer defaults it over to the drivers side leaving passengers side blowing warm. (dealer says) Truck has 23,000. miles. Freind of mine 2000 Ram has same problem. Wonder if this is common? any one hear of such ?

 

[DPKetchum]

No such thing as going to default drivers side. The system is not smart or really even any contol of it through the computer! CHEZZ! It just runs low and not enough freon to cool the entire evaporator assembly. Now the freezing up can and then again can be of the same issue. More then one thing can make one freeze. Low charge,bad or wrong location temp probe(fin temp sensor) etc.

 

[Bob4x4]

My 2003 Ram quad cab has a very slow leak in the evaperator . In shop now. When the system runs low on free-on the computer defaults it over to the drivers side leaving passengers side blowing warm. (dealer says) Truck has 23,000. miles. Freind of mine 2000 Ram has same problem. Wonder if this is common? any one hear of such ?

Tell your dealer. . bs. One evaperator in your truck. However the evap will not be a uniform temp from side to side if the r-134 is low.



Bob

 

[agfckrowe]

Drove the truck locally today and yesterday, had it on high with outside air AC, its working hard to keep it cool. Have to drive 3 hours to Memphis and 3 hours back tomorrow so that will be a delightful (ugh, Yuck!) test.



David, what dealer do you go to with your truck. Sound like we need to double up and take our trucks to the same place and put some pressure on them.



KR

 

[LesStallings]

As others have said, freezing up may be due to low R134a charge as that is one of the symptoms.



Other things to consider are how you use the system. If you have warm, moist, outside air coming through the evaporator, it is reasonable to expect it to freeze. Several things can be done to avoid freeze up. 1) Do not set the temperature control to the absolute highest setting. At that setting the compressor does not cycle on and off, allowing moisture to freeze and never "defrost". I recommend setting the temperature just short of max and on long trips, reduce the temperature setting as the entire cab cools off. 2) On humid days and very hot days, always choose the recirculation setting. This keeps the humid air outside. As air is cooled, moisture in the air condenses and runs out the drains, assuming it does not freeze. Once the air inside the cab is dehumidified, freezing of the evaporator is much less likely. 3) Keep air moving through the evaporator. If it is recirculated, dehumidified air, the evaporator will be operating closer to the cab air temperature and therefore reduce the chance of freeze up. This means you reduce the temperature setting as the cab cools, not the fan speed. If fan noise is a factor, try to keep as high a fan setting as acceptable.



Try it. I think you will have fewer problems.

 

[Patriot_RAM]

agfckrowe, I use Lewis in Fayetteville. Overall, I've had good luck with them. You?

 

[agfckrowe]

Well, I got it to work right. I turned the temp setting to several clicks less than full cold. Once the air got cool, I used the recirc setting but several minutes before I got home I used the outside air setting to prevent mold and musty smells? I tried to take in everyones suggestions, I don't know if I got it right but the 3 hours there and 3 hours back were nice and chilly the whole time.

Thanks to everyone who has responsed to my thread!

KR

 

[Crunch]

Oh the nasty funk smell if you leave it on recirc/max is sweat/bad breath. my old roomate did a test for GM on this they now equip their Cadillac with a switch that runs fan on low for couple minutes after shut off so that fins are fully dried and smell goes away. I try to do this every couple days when it is cool in the morning (run vent only to dry system completly).

I usually drive with the A/C on recirc, but keep the fan/blower on low because the slower the air moves over the coils the cooler it gets. My practice has been to turn off the A/C a few miles before I get home, crank the fan up and set the air to fresh to dry out the vents. I still get an occasional funk smell from the vents when I turn the A/C on. Does anyone know where the fresh air first enters the system? I'd like to send some Lysol up the pipes while the fan is running to clean the system out.

 

[DPKetchum]

Lysol from my experiance dosen't do much. The spores grow on /in the evaporator and in the case. They actually make a kit that a tube inserts up in the system that kills the spores. Fresh cuts down on spore growth.

 

[Billy Golightly]

I'm having the exact same problem, except it happens usually in just over an hour. I usually turn the heat on full blast for just afew seconds and then switch back over to the cool, but it stops blowing not even 5minutes later again. The temperature control is about horizontal over in the blue, so its not like its wide open. Recirculating the air doesn't seem to help any. A REAL pain in the you know what on long trips. When I took a 750 mile trip to Indiana back in June I ended up riding with the windows rolled down 3/4 of the way

 

[Elite1]

My truck has about 60K miles on it, have been on several long hot trips without any AC problems. Now all of a sudden this issue... makes me think it must be some bad electronic device, or maybe the freon needs to be changed out... seems there must be an easy fix?

 

[navyramman]

Same that as Elite 1, The only fix and it works right a way is to turn off the truck and start it back up. and everything works right. It must be in the switch or something else. can not be frezzing up or bad freon.

 

[Patriot_RAM]

Mine worked fine and suddenly started freezing up. Turning the truck off didn't fix mine, but it was definitely freezing up. Just to update -- I got a coolant charge last week and the problem is gone. It was quite a bit low.

 

[Elite1]

Mine worked fine and suddenly started freezing up. Turning the truck off didn't fix mine, but it was definitely freezing up. Just to update -- I got a coolant charge last week and the problem is gone. It was quite a bit low.

That post of mine is pretty old, but that is the same problem I had, a little low on freon (or whatever they call it now) & it has worked great ever since.

 

[COBRAJET]

The problem is in other vehicles as well. My wife drives a 2004 Ford Expedition that had the same problem. We took it back twice under the 36K warranty. They evacuated twice and refilled at 17K and again at 35K. The problem never got better. It does not go on long trips too often. It started the same BS again this spring and we took it back again with 52K. At this time we were explained that Ford knew about the problem and had issued a TSB and a kit to rectify the issue. The dealer performed the fix and we have had no issues. We just got back from a 4400 mile trip in it and did not have one problem. I was mad because Ford would not fix it for free since the truck had more than 36K on it... . even though it showed a track record of an AC issue. To top that off the extended warranty... not from Ford would not pay either since Ford had issued a TSB... . essentially accepting blame as far as the warranty company was concerned. The kit was $115 with $155 in labor. At least it is really really cold now and does not freeze up. Works way better than the truck driven below.

 

[JLitton]

Amazing... I love this site. I just got back from vacation and had this problem twice. However, my issue is also the lack of volume of air coming through the vents. It has happened while pulling my 5th wheel through the Carolina heat and humidity. I turned off the fan and AC repeatedly and finally it got cold and the volume of air was back to normal. It seemed to me that something was stuck in the duct work. or maybe a flap was stuck shut or something.

 

[DPKetchum]

Frozen up. Turn off the AC for 5 minutes,leave fan on or not. Then turn ac back on. If you stop and turn ac or truck off you will see a LARGE amount of water drain out of it as it thaws. The evaporator turns to a block of ice and air flow can't pass throught it.

 

[GHatcher]

A/C Problems

Ok... I live in the hot humid heat of the South Carolina and I'm having the same problem. From all the posts, I'm going to get the freon checked to see if it is at the correct psi. But just like everyone else I have cold air blowing from the vents, just the air flow is decreased considerably with the fan speed on Max, after say an hour or so. An A/C service tech told me if the freon was too low this could possibly be causing the system to freeze up, which would in turn restrict the air flow. I'll let you know the results... .

2004 Ram Quad Cab 39K

 

[GHatcher]

Ok... I live in the hot humid heat of the South Carolina and I'm having the same problem. From all the posts, I'm going to get the freon checked to see if it is at the correct psi. But just like everyone else I have cold air blowing from the vents, just the air flow is decreased considerably with the fan speed on Max, after say an hour or so. An A/C service tech told me if the freon was too low this could possibly be causing the system to freeze up, which would in turn restrict the air flow. I'll let you know the results... .

2004 Ram Quad Cab 39K

Had the AC checked. The R-134A Freon was low at around 12 psi. The Service Tech added the R-134A to about 35 psi... no more problems with the air. He said the coils were freezing up because of low freon. The only thing now is that there must be a slow leak somewhere, anyway I'm back cooling.

 

[Scrappy]

I had the same problem w/mine, the dealer replaced and relocated my fin temp sensor last summer and all is good since.