A/C blowns ice cold when driving, but sitting at idle, not really cold.

[99VPRGTS]

Hey all, anyone got some insight to this problem? I am about to go in and have everything evacuated and then reserviced. Is there anything else it could be? The car does get a little hot at idle (about 215-220) in FL heat but I was told that this was normal operating temp by another Viper owner. Fans come on also. When cruising, A/C works fine and has since I bought the car a year ago. I have a 1999 GTS. Thanks.

-Brent

 

[dave6666]

It is working perfectly like mine always has.

Dave, 2001 GTS, living in Texas, where 110 degrees is a Tuesday.

 

[Tom F&L GoR]

Hey all, anyone got some insight to this problem? I am about to go in and have everything evacuated and then reserviced. Is there anything else it could be? The car does get a little hot at idle (about 215-220) in FL heat but I was told that this was normal operating temp by another Viper owner. Fans come on also. When cruising, A/C works fine and has since I bought the car a year ago. I have a 1999 GTS. Thanks.

-Brent

Find the sight glass and see if there are bubbles. Having a partially functioning AC means you can add some refrigerant rather than evacuate and recharge.

 

[dave6666]

Find the sight glass and see if there are bubbles. Having a partially functioning AC means you can add some refrigerant rather than evacuate and recharge.

It has been pointed out in a previous AC thread that r134a needs to be really moving through the pipes to do it's job. 1500 rpm was the minimum suggested engine speed. I would check the sight glass both at idle and have someone bump the rpm's up for 30 seconds or so and check again. While still at 1500 rpm.

 

[99VPRGTS]

I did try and service it myself with R134, I think where I messed up was not having a steady idle at 1100 (like the manual says). I tried keeping it steady with my foot when I should have just turned the adjustment in on the throttle. I forgot to mention that when I filled it with a 20 OZ can, bubbles still flowed through the glass. I didn't want to put any more in because overcharging it wouldn't help me at all.

 

[dave6666]

I have also seen it mentioned that even at "fully and properly charged," bubbles still in the sight glass. If it is not blowing condensate smoke out the cabin vents then you are probably OK with your charge. Condensate smoke comes from the evaporator freezing due to a low freon charge. That's when I know to charge mine. Which if my car stays at a can or two a year leak rate, I call the permanent fix for that adding a can or two a year.

 

[Sweet Ride]

Check your condensor as well. Blow it out with compressed air. If you really want to clean it out, loosen the radiator and move it back a bit. A lot of crap can get packed between the condensor and the radiator causing poor cooling and poor a/c function.

 

[GTSnake]

I did try and service it myself with R134, I think where I messed up was not having a steady idle at 1100 (like the manual says). I tried keeping it steady with my foot when I should have just turned the adjustment in on the throttle.

It's probably not a good idea to be adjusting your idle with the set screw. The PCM controls idle speed. It should be at 700rpms.

 

[ViperJohn]

Is your 99 GTS an ACR? My understanding is the ACR A/C doesn't work as well at idle due to the different oil filter adapter.

 

[jdeft1]

At 1100 rpm, 80deg or below outside air temp, doors/windows open ... you should see no bubbles in the glass. If over 85deg. you should. If there's no cold air at all check to make sure the compressor is turning... If you look at the compressor, also look at the line fittings on the compressor, checking for oil seepage... I understand they tend to leak...

This holds true with most 134a auto. systems so check your other cars too.

- J

 

[Martin]

It actually sounds like it's working fine to me - that seems to be how mine has worked since day one. Unless you have a lot of air passing over the condenser, not much heat gets removed from the system.

 

[vip06]

That's the same way mine works, when moving cold air but at idle it's just cool air.

 

[99 R/T 10]

Is your 99 GTS an ACR? My understanding is the ACR A/C doesn't work as well at idle due to the different oil filter adapter.

Say what?!


Not sure that the oil filter adapter has to do with the A/C.........................

 

[Martin]

Say what?!


Not sure that the oil filter adapter has to do with the A/C.........................

There was actually something about ACRs and the A/C. It was a long time ago, but I remember something about there being a valve in the oil filter adapter on standard GTSs that bypassed the oil cooler when the A/C was on. On the ACR cars, the oil would always flow through the cooler and would therefore affect the A/C performance.

 

[dave6666]

Say what?!


Not sure that the oil filter adapter has to do with the A/C.........................

From Jon B on the ACR adapter thread of earlier...

"The 1999-02 ACR was designed for track use, NO A/C, no radio, etc. So the ACR -all of em, even with A.C- routes oil 100% of the time thru the oil cooler. No restriction in-line. This results in cooler oil, and pressures at +4~7psi. In heavy traffic this hotter oil cooler can heat up the A/C condensor, and it can temporarily trip off-line. No harm just warm."

 

[plumcrazy]

yup, thats what DLM told me yesterday when i asked if i should consider the adapter for mine.

its a double edge sword and depending on the driving/racing its not as good. for my type of driving/racing its not gonna help as much and i do some city driving and sitting in traffic where it would be a problem.

 

[99 R/T 10]

From Jon B on the ACR adapter thread of earlier...

"The 1999-02 ACR was designed for track use, NO A/C, no radio, etc. So the ACR -all of em, even with A.C- routes oil 100% of the time thru the oil cooler. No restriction in-line. This results in cooler oil, and pressures at +4~7psi. In heavy traffic this hotter oil cooler can heat up the A/C condensor, and it can temporarily trip off-line. No harm just warm."

Thanks Dave. Doesn't seem to be a big deal.

 

[dave6666]

Thanks Dave. Doesn't seem to be a big deal.

But I do like how Plum captured the thought above, that it is not for everyone. I have taken it off of my mod list as I agree with Plum/DLM.

 

[Viper Wizard]

I did try and service it myself with R134, I think where I messed up was not having a steady idle at 1100 (like the manual says). I tried keeping it steady with my foot when I should have just turned the adjustment in on the throttle. I forgot to mention that when I filled it with a 20 OZ can, bubbles still flowed through the glass. I didn't want to put any more in because overcharging it wouldn't help me at all.

Hey Brent,

Try it this way: forget the 1100rpm, do it at an idle, A/C on [all the way to the left!], full fan, windows open. You will need to put a little more in the system and watch the sight glass with a flash light for at least two/three minutes [each time you add 134]. If you still see bubbles, add a little more until there are no more bubbles. And yes the A/C will be colder going down the road then sitting in traffic, this is normal!

If you'd like to call me, I can walk you through it.
914-763-3136

 

[jdeft1]

Yep... I'm with the Wizard. Auto A/C is a bit strange because the speed of the compressor varies. Most designs call for 1000 rpm w/80deg ambient, no bubbles... should see 45f +/- from the vents with full fan and open car...

my .02