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A/C Issue


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Posted

95F in Ohio today and the A/C wouldn't go lower than 70F. Yesterday, when it was 92F it was blowing around 49F. The dealer has recharged the system once. I"m about out of warranty, and it is two weeks before I can get it in again. Is there anything I can check to get a feel for what the issue is and prevent the dealership from screwing me? The right two vents (passenger) always run wamer than the driverside. Manual temp controls.

 

Jansen

Posted

If you have a low side pressure gauge (~$20 at Wal-Mart) you can tell us the static pressure in the system with the engine cold, the ambient outside temp., and operating pressure range with the engine running.

 

Is your clutch cycling every few seconds?

 

DEWFPO

Posted

Ok, tonight I went to the gym and the a/c was pumping out 46F air. I'm a little confused. Since last summer the driver side was a constant 49F, the passenger 52F. Now the driver side would go not colder than 70F earlier today then 46F. What is causing the fluctuations?

 

Jansen.

 

I checked and the clutches are not cycling faster than they used to.

Posted

humidity is the same as heat to an a/c. it is called latent(hidden) heat.

 

If your unit blows 46 degree air at idle, you are on spec. if it is very humid it might be a bit higher.

 

To really check, see if the accumulator is cold. if it or the line from the evaporator to it (firewall side) is cold, you are great.

 

If the a/c is condensing lots of water and dripping under the car, the unit is working great.

 

If you are comfortable after a few minutes of cruising, the unit is working great.

 

Lots of people look for trouble with a/c units that are really fine. The main concept to look for is accumulator temp. if it is cold, you are ok. adding refrigerant to a properly charged unit will raise all temperatures.

 

Ken :D

Posted

I don't know then. Today after work it was back between 60F and 70F at idle with outside temps between 92F-95F. I popped the hood and saw condesation on the lines. I'll check tomorrow to see if the line is cool coming into the firewall.

 

Jansen

Posted
I don't know then.  Today after work it was back between 60F and 70F at idle with outside temps between 92F-95F.  I popped the hood and saw condesation on the lines.  I'll check tomorrow to see if the line is cool coming into the firewall.

 

Jansen

 

 

 

 

 

does yer fan clutch work??

 

Automotive AC needs good air flow across condenser, for instance does it work better when your driving down the hiway but outlet temperature warms up when your idling.

 

 

is it a 134 A system?? these are even more sensitive to air flow across condenser and work better with good air flow and higher compressor speeds.

 

you have to give an a/c system time to stabilize, like any other mechanical device it warms up and becomes more efficient after it has been running for 10 or 15 minutes. Its unreasonable to expect an ac system to blow ice cold air when its more than 100 degrees inside a vehicle thats been sitting out in the summer sun and all the interior parts are that temperature,you could have a 35 degree evaporator but by the time that air is distributed thru the 130 degree plenum and ductwork its going to warm up. that AC unit has to absorb all the interior heat in that vehicle and move it outside before it will start to cool off the vehicle.

 

so you

gotta give it a chance, it might be working as good as it ever will.

  • 2 weeks later...
Posted

Guess who is getting a new A/C compressor.......ME! Dealership called me yesterday and said they had a loaner waiting for me and that I can expect the truck back on Monday.

 

Mixed feelings on this one though. It's Good that the dealership found the problem, but it adds to a long list of issues with this truck. With so many issues before the warranty perioud is up (33,000 miles now), I'm scared to think of what this truck will cost me, good to know that it was made in the U.S.A. I hear the Japanese brands calling, considerin toyota and nissan make theirs in the U.S.A.

too.

 

I'm going to draft a letter with all the issues that needed fixed (2nd time for A/C) and ask GM to provide and extended warranty. I have around 15 items fixed now in 19months of ownership. That amounts to approximately 18 days with out my truck. If they don't do something for me, I'm going to send them a picture of my new Toyota.

 

 

Jansen

Posted
humidity is the same as heat to an a/c.  it is called latent(hidden) heat.

 

If your unit blows 46 degree air at idle, you are on spec.  if it is very humid it might be a bit higher.

 

To really check, see if the accumulator is cold.  if it or the line from the evaporator to it (firewall side) is cold, you are great.

 

If the a/c is condensing lots of water and dripping under the car, the unit is working great.

 

If you are comfortable after a few minutes of cruising, the unit is working great.

 

Lots of people look for trouble with a/c units that are really fine.  The main concept to look for is accumulator temp.  if it is cold, you are ok.  adding refrigerant to a properly charged unit will raise all temperatures.

 

Ken :cheers:

 

 

 

 

I dunno. I'd get it checked. My unit blows in the 50s regaurdless of heat, humidity ect. I live in Houston, so lots of both. In mild humidity and low 90s will get into mid 40s.

Posted

I do not feel like they would give you an extended warranty. I have a 98 with 170k on it and no real problems at all (until it started oil fouling the #6 plug), but I was ready to put a new motor in anyway. They will tell you something like they have lived up to the warranty promised when you bought the truck, but in my expirence, I have not seen many vehicles have a whole lot of problems once they get out of warranty.

Posted

I don't know. My uncle has a 91 reg cab,8ft bed with 4.3LV6 and was at or over 250,000 miles before it was wrecked. I look at mine and there is no way I'm going to get that. It bothers me that I've had all these issues and, as if I didn't pay enough already, in a few short miles I've got to pay for repairs that are from bad builds.

 

Oh well.

 

 

Jansen

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