'04 GT A/C Question

[BWCAVibe]

Hello,

Recently, the A/C does not blow cold when the button is pushed. I read Ken's post from July, 2014 on his '03 GT with pretty much the same issue, and sent him a PM to see if that took care of the problem. However, mine does one thing different and that is when I push the A/C/ button, the engine revs down slightly, not up as Ken indicated with his '03. So I was wondering if this indicates a problem different than the A/C clutch/coil? I have a voltmeter so I can test the one wire plug into the compressor.

The A/C button light comes on, fan blows air, but not even close to cold. I assume this is an issue for winter driving as well for when the defrost is on? Not that this matters for the A/C issue, but woth mentioning, the thermostat is likely stuck open as the temp gauge never rises past the second bar from the bottom. Maybe time to kill 2 birds with one stone?

Thanks

[BWCAVibe]

Hi,

A follow up on this 10.2014 thread...

The local repair shop I trust informed me the A/C compressor on my '04 GT is caput. It is not the clutch, which is what I was hoping. I was quoted $1000, which includes replacement of the A/C "filter", which I am not sure what that is, recharge, etc. Anyway, the compressor replacement does not look too intimidating as long as the mounting bolts come out somewhat easily. I know I can find other threads on replacing the compressor. Does anyone have a particular thread that may be the best to follow? Any other recommendations, such as do not do it yourself or anything like that?

A new compressor is about $300...not sure about the cost of the "A/C filter" they referenced? I am not sure how much a recharge would be. Do I want to try to do the recharge myself? If I cannot do this myself, I may not get it fixed. We have hot days in Northern WI, but not too many that I am constantly using the A/C in the summer.

Thanks for any suggestions.

[vibrologist]

I want to delete a post to avoid double posting. I don't see a "delete" option.

[vibrologist]

A/C work is best left to specialists (IMO).

1. The refrigerant must be removed. There are environmental laws that require the use of a recovery unit.
2. After replacing all the parts (evaporator, condenser, compressor, accumulator/dryer (I bet that is what he calls the filter)) and all the seals/o-rings the system must be evacuated with a rotary vane vacuum pump in order to get all remaining moisture out. You need a vacuum pump and gauges to do that.
3. Then you need to test the system for leaks. You could disconnect the pump and see if the vacuum stays the same over night. The shop would likely use pressure to test for leaks and then apply the vacuum.
4. If the system is seal it is time to fill it with refrigerant. There is a good chance to mess up by getting moisture in the system.

One grand seems a bit high, but he wants to make sure it is right the first time. By shopping around you may get the parts a bit cheaper than he is charging for them. I think I would get a second estimate from another reputable A/C specialist. If you buy your own parts buy only high quality.

[trb]

That is a lot if it is just a compressor/ dryer replacement. But they can charge a lot for AC work since most people need it. Is the compressor just bad, or did it possibly grenade and allow metal particles flow into the hoses? If so, then they have to flush the lines and remove all contaminants or you will end up replacing the compressor again. I could see that price if that is what they are doing, or if they are replacing other parts too.

I replaced the complete AC system on my Mustang several years ago for about $700 doing the work myself. That's replacing EVERYTHING.

An AC Delco compressor on rockauto.com is about $240 and the receiver/dryer is under $30. r134a refrigerant is probably $25 or so and oil for the o-rings. That's ~$300 parts and $700 labor! If you wanted to do it yourself and it didn't grenade, it is not that hard if you have some wrenching experience. Auto Zone and a few other parts places rent out the gauges and vacuum pump for you to use. While it is generally suggested to recover the existing refrigerant, the r134a used now is not as damaging to the environment as the r12 used before. I leaked about 6 cans of r134a tracking down a slow leak. I got to be an expert on the vacuum and refill process!

Main thing about AC work is to make sure the lines are clean, and all of the moisture is boiled out of the lines with the vacuum pump. I left the vacuum pump on mine for several hours to make sure, often overnight.

[BWCAVibe]

Thanks trb and Vibrologist. The process sounds like someting I could do, but I am just not sure if I want to...there is quite a bit to consider. I feel good I was able to replace the e brake cables and e brake shoes this winter so maybe I can feel good about saving some $ on that and move on. The shop that gave me the quote is really the best in Town. They always have diagnosed real well and have given me a real accurate estimate for other stuff.

[lannvouivre]

Thanks trb and Vibrologist. The process sounds like someting I could do, but I am just not sure if I want to...there is quite a bit to consider. I feel good I was able to replace the e brake cables and e brake shoes this winter so maybe I can feel good about saving some $ on that and move on. The shop that gave me the quote is really the best in Town. They always have diagnosed real well and have given me a real accurate estimate for other stuff.

You can have them recover the refrigerant and then fill the system when you're done. It's not so bad to do, I have removed mine from the engine and it's three bolts (mine were seized tight with corrosion). The line removal is also easy. Make sure you replace the O-rings.