I have a situation that has me puzzled. I have a 1997 Silverado and the A/C is not cold. I checked the system and it shows that it is fully charged, however, there is no cold air. Then the line coming from the pump is not cold. How and it be full, but no cold?

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Current:
1985 300D aka Miss Margaret
1991 300SE aka Alarice
1995 SL320 aka Samantha
1997 K1500 Silverado
Past:
1999 E300 ex-wife got it and let her son ruin it
1984 190 2.3 ex-wife got it and let her son destroy a great car
1985 300D (CA version) aka Maybelline lost to deer at high speed.
1981 300D aka Madeline (went to salvage at near 400k) rusty, yet best car I ever drove
Wishlist:
McFarlan TV6 (only a few privately owned)
ReVere with Rochester engine
1917 Premier (only one left)

Well, to start with are you seeing the compressor clutch engage?

The line coming FROM the compressor should not be cold. The line going TO the compressor is the one that should be cold. It is the larger one.

How are you determining that the system has a full charge?

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

The pump is working. I have a small charge unit with gauge. Both lines are the same size on the vehicle. Both lines are hot from the engine heat...nothing is cool

__________________
Current:
1985 300D aka Miss Margaret
1991 300SE aka Alarice
1995 SL320 aka Samantha
1997 K1500 Silverado
Past:
1999 E300 ex-wife got it and let her son ruin it
1984 190 2.3 ex-wife got it and let her son destroy a great car
1985 300D (CA version) aka Maybelline lost to deer at high speed.
1981 300D aka Madeline (went to salvage at near 400k) rusty, yet best car I ever drove
Wishlist:
McFarlan TV6 (only a few privately owned)
ReVere with Rochester engine
1917 Premier (only one left)

It sounds as if you are only able to check low side pressure. You REALLY need to monitor both.

One other thing. On the Chevy trucks I've messed with, it is not uncommon for them not to get enough airflow at idle. The fan clutches wear out or something. You can easily tell that this is going on with manifold gauges, because you see the high side pressure go so high you feel like you need to hide behind something.

Until you can monitor both sides, you are handicapped in trying to determine the problem.

Hope this helps.

__________________
2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

Subcool, Superheat, Sensible Heat and Latent Heat of Evaporation. Know these terms and the AC world will be revealed to you.

Where is the refrigerant and what is it doing?

We have an S10 we use on the farm that the a/c compressor clutch pulls in but there is no pressure differential on a properly charged system. This is a sign the compressor is no good.

__________________
Jim