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1998 GMC Yukon Repair Question


Topics covered: Condenser, Expansion valve, Orifice tube.
Mileage: No information provided.

Asked on August 25, 2012

Expert needing a answer guys

Expert here needing some help with a/c
my truck is a 98 yukon... had some a/c problems causing the high side to be super high and kick out.. got my blockage fixed but my high side is still running up there pretty high 350-375. have i blown my compressor? system has been flushed oiled and vac'd and charged with the correct amount of r134.

Answer

Replied on August 25, 2012

ps new condensor new reciver dryer new orifice tube.

Tiny Response from carolinacarconnection (expert)
69 answers provided
Replied on August 25, 2012

What is the low side?

Tiny Answered by KHLow2008 (expert)
39,862 answers provided
Replied on August 25, 2012

55-57 psi ambent temp is about 96-98

Tiny Response from carolinacarconnection (expert)
69 answers provided

Replied on August 26, 2012

There seems to be too much freon in system.

Tiny Answered by KHLow2008 (expert)
39,862 answers provided
Replied on August 26, 2012

Its not a overcharge issue.. it started running high when the first 8 ounces were added

Tiny Response from carolinacarconnection (expert)
69 answers provided
Replied on August 26, 2012

Was the system evacuated? If it is not overcharging then there is air in system. Both low and high are showing high pressure.

Tiny Answered by KHLow2008 (expert)
39,862 answers provided

Replied on August 26, 2012

Yes the system was vacd for 45 minutes and pulled to 29hg v. From what i understand 55 psi on the low side is fine for 100 degree ambient

Tiny Response from carolinacarconnection (expert)
69 answers provided
Replied on August 26, 2012

Here are the specifications.

Referigerant is 36 ozs without rear unit and 64 if with rear unit.

Tiny Answered by KHLow2008 (expert)
39,862 answers provided
Replied on August 26, 2012

At 2000 rpm thats right where im sitting on the low side.. high side shoots sky high and kicks out

Tiny Response from carolinacarconnection (expert)
69 answers provided
Replied on August 26, 2012

If you are sure the expansion valve, condenser and referigerant is correct, the other thing that can cause this would be the condenser is not being cooled sufficiently. Try spraying a fine shower of water onto the condenser and repeat the test. I don't think it is the compressor that is faulty because a bad compressor would not be able to push very high pressure, unless the relieve valve internally is stuck and supplying excessive pressure.

Tiny Answered by KHLow2008 (expert)
39,862 answers provided