HELP! Sweating To The 03

gltech · June 2, 2006

I have two suburbans at the moment, an 03 I just bought, and an 01 that I've had for a while that I'm going to sell. The 01 has the non-auto climate control, and the 03 has the auto version. I can set the 01 to coldest for front and rear for about 10 minutes in 90+ degree weather and I actually have to turn it down. In the same conditions, I have to run the 03 on 60 and recirc for front and rear continuously and it's just barely tolerable. It seems muggy in the car, like the humidity isn't being removed.

I took it to a dealer and a tech did the test with the little thermometer in the vent, and said it was about 50, and that it was in range. He even had the service manager confirm his opinion. The tech said he could suck the system dry and recharge it, but that it might end up worse than it is now.

I am hot-natured and miserable. Could I have R12 in the 01 and R134 in the 03? How much difference between the two? When running the coldest settings, you can't hold your hand in front of the 01 vent for long, while the 03 just blows "sort-of" cold. Can I put R12 in the 03? Are the components and lines suitable? Any other suggestions?

Thanks,

Glenn

2kwolfgang · June 2, 2006

This is indeed strange... I'm pretty sure GM has been using R-12 in full size trucks since around 95. My 99 Sierra blows VERY cold air but I bet the inner workings of the system are probably not much different then your 03.....

ChevyTech007 · June 2, 2006

You have R-134A in both. I would say you have a problem with the 03. Would have to know what the pressures were to help. One thing that I have seen when it gets hot, and is easy to overlook is the fan clutch.

gltech · June 2, 2006

Thank you very much!

Turns out I took it by a local independent guy I know, he slapped his gauges on it, said the refrigerant was low, tried to add some, and the compressor started making a griding noise. He immediately shut the car off, and sucked all the refrigerant out, then added new back in. Now it blows real cold like the 2001. So all's well for now, although he said my compressor was awfully rattlely/noisy, which he said could be a sign of it dying.

One odd thing to me was that when he hooked up his gauges, the only place to hook them were two receptacles that were about 8 inches away from each other on the same line (the "high" side of the front feed). I thought you normally hooked one on the "high" side and one on the "low" side. He seemed kind of puzzled himself.

Thanks again,

Glenn

ChevyTech007 · June 3, 2006

Sounds like you need a new compressor. The orifice is between the two service fittings.

pm26 · June 4, 2006

This is indeed strange... I'm pretty sure GM has been using R-12 in full size trucks since around 95. My 99 Sierra blows VERY cold air but I bet the inner workings of the system are probably not much different then your 03.....

<{POST_SNAPBACK}>

You mean R 134.

2kwolfgang · June 5, 2006

This is indeed strange... I'm pretty sure GM has been using R-12 in full size trucks since around 95. My 99 Sierra blows VERY cold air but I bet the inner workings of the system are probably not much different then your 03.....

<{POST_SNAPBACK}>

You mean R 134.

<{POST_SNAPBACK}>

Yes I do...

gltech · June 7, 2006

I've decided to replace my compressor so I don't get stuck somewhere with no a/c. I have the GM service manuals, and it says to replace the drier/accumulator, the orifice and all the o-rings when replacing the compressor. The orifice between the service connectors is for the front unit, right? Is there another orifice for the rear unit I should replace as well?

Glenn

ChevyTech007 · June 7, 2006

You should replace the expansion valve on the rear unit if there is metal in the orifice. The orifice is between the fittings.

gltech · June 7, 2006

Thanks ChevyTech. According to my service manuals, that looks like that will be quite a job if I have to do that (draining coolant, removing the aux heater core and evap core).

Question: Is the "orifice" just another term for expansion valve? In other words, oes it act as the expansion valve for the front unit?

ChevyTech007 · June 8, 2006

It does the same thing in the sense that it reduces high pressure to low pressure. An orifice is just a fixed restriction but an expansion valve is a veritable restriction based on the outlet temp of the evaporator. I would check the front orifice before I replaced the rear valve. If there is not much metal in the orifice I would take a chance with the old valve. If you do have to change it, you can vise grip the heater hoses near the rear core so you do not have to drain the whole system.

C & A s Dad · June 8, 2006

Glenn, don' t know if you have fixed it yet or not but I would add a couple of suggestions. 1) Use a NEW compressor only not a reman. 2) Flush the system with an approved flush 3) I would also suggest a good Inline filter.

I am in the Auto Parts industry and Compressors have been a big issue for the past several years. If a new comp is used, your system is flushed properly and the proper oil is used, you will have no issues.

My Yukon XL is an 02 and I cannot believe how cold the air is. I can run the rear for only a few minutes and then my kids are asking to turn it off.

I drive a Dodge Caravan for work each day and the AC system is terrible in hot weather as it is in many front wheel drive cars. I added a can of Polar cool from Quest Products and it dropped my vent temp by 4 degrees. This stuff is not a sanke oil it is simply a frction modifier that helps the comp work better. I have not used it in my Yuk because I have not needed it.

Some of the Techs may be able to tell us if there is any issue with this chem but we sell a lot of it and to my knowledge have had no issues.

Good luck with your new A/C system

gltech · June 9, 2006

Thanks everyone. C & A s Dad, I'm getting a compressor for $150 from a company that parts out new cars damaged in shipping. It should be good as new, but I'll have to figure out the "oiling" thing.

When you say "flush the system", do you mean the A/C system? I've never heard of that. How do you do it and what do you use?

Where do you get an inline filter and where do you install it?

Your 02 sounds like my 01 (see my first post in this thread). Amazing A/C. Coldest one I've ever seen. Even in that big vehicle, 5 minutes on high and I'm having to turn it down.

Cheers,

Glenn

C & A s Dad · June 9, 2006

Glenn, please understand I am no Technician but do make my living selling auto parts to them.

The Oil: I do not have the capacity specs with me right now but I am sure that you will need to use PAG oil and I believe the viscosity should be 150. You will need to check on the amount to use. Of course, if you are buying a used comp it will have oil in it. I would suggest draining it and refilling it so you know exactly what you have.

The flush: Yes, I do mean flush the AC system. This is critical. There are a hundred flushes and methods, we have even seen people use brake clean, don't do that. We sell an aerosol can from Super Cool called extra flush and I have had several Techs tell me it does and excellent job and works as well as many high dollar flush guns. The mfg code is CCM and the Part # is 6977.

The inline filter: Again, we believe this is a vital piece, especially in a system that has failed and released metal trash into the system. The unit we sell is also from Super Cool and is very high quality screening device that goes in a metal line. The mfg code for us is EQP and the part # is 13128.

134A: There are different grades of Freon also. I would strongly suggest that you look for SUVA 134A that is produced by Dupont. There are other quality freons out there but there is also some offshore junk.

I did not notice where you are from but I work for CARQUEST Auto Parts. Hopefully there is a store in your area but as I have said before, I am not promoting our co. or products on this forum and I am sure that you can find these products at other stores.

Good luck to you. I can tell you that we (CQ) will always refer a DIYer to a professional Technician for jobs such as A/C work. Not to say that you cannot do it yourself, just take every precaution.