GM

GM repair problems? Ask a GM repair expert now.

Ask an Expert,
Get an Answer ASAP!

Chevy silverado 1500 hd: intermitent..mornings..the AC..blows cold air…

Customer Question
I have an 02 chevy...
I have an 02 chevy silverado 1500HD that has an intermitent problem with AC. In the mornings when I start my truck the AC always blows cold air within seconds after the engine is running. In the afternoon when the outside temperature reach about 95 or above I will have to drive my truck for 1 to 3 miles before the AC blows cold air. I have had it in the shop and they replaced HVAC temp door actuator. Did not help.
Submitted: 7 years ago.Category: GM
Show More
Show Less
Ask Your Own GM Question
Answered in 2 hours by:
8/1/2010
GM Mechanic: Mark, ASE Certified Technician replied 7 years ago
Mark
Mark, ASE Certified Technician
Category: GM
Satisfied Customers: 847
Experience: 34+ yrs Dealership Exp. - Fully State & ASE Certified - GM Master & GM World Class Tech
Verified
Greetings, my name is Mark.

I found this bulletin that may help. Please keep in mind, bulletins are NOT "recalls" or are they even, .... "every vehicle has this problem".

Bulletins are just "helps" to the techs should they encounter a known issue. Read over the bulletin and see what you think.

If you should happen to go back to the dealer, you might get further in "gently" telling them you heard somewhere that there might be an issue with the AC accumulator. You might even mention that you heard there was a bulletin addressing your issue.

I don't know why, but dealership's tend to frown on being told there is a bulletin. Most likely because there is so much FALSE information out there, that most of the time, it is bogus info. the customer supplies. However, your dealership should have done the homework on this.

AND, maybe they did. Maybe they saw this bulletin and didn't think it applied to your vehicle. Maybe they followed the diagnostics and it didn't lead to the accumulator. Or maybe there was a loss of communication between you, the service writer, and the tech. I don't know. I don't want to throw darts at anyone. The diagnosis and repair now-a-days is terribly complex and just not an easy task.

Anyways, I hope this at least helps shed a little lite on your subject.

#02-01-38-007C

Poor A/C Performance - A/C Will Not Blow Cold Enough (Perform A/C System Checks, Replace Accumulator, If Necessary) - (Jul 27, 2004)
Models:2002-2004 Chevrolet Silverado
2002-2004 GMC Sierra
with 6.6L Diesel Engine (VINs 1, 2 -- RPOs LB7, LLY)
and Denso A/C Compressor


This bulletin is being revised to add part numbers for the hose, bracket and insulator to the Parts Information. Please discard Corporate Bulletin Number 02-01-38-007B (Section 01 -- HVAC).


Condition

Some customers may comment on less than desirable A/C performance, especially when the ambient temperature is above 32°C (90°F).

Correction

Perform the following A/C system checks and replace the accumulator with P/N 89018601, if necessary. This new accumulator requires the accumulator bracket, the accumulator insulator and the A/C suction hose to be replaced also.

Check for A/C system leaks.
Check the A/C system for proper refrigerant charge. This requires recovering the refrigerant to determine charge in system. Refer to Refrigerant Recovery and Recharging in the HVAC sub-section of the Service Manual.
If no leaks were found and the A/C system is charged to specification, replace the accumulator using the procedure listed below.

If normal diagnostics do not lead to a correction, then perform the following A/C system checks.

  1. Re-calibrate the actuators. Refer to Recalibrating Actuators in the HVAC System - Manual/Automatic sub-section of the Service Manual (SI Document ID #904666).
  2. Inspect the lower A/C condenser deflector for proper installation. The deflector should be positioned at the lower part of the condenser and extend forward into the top of the front bumper and below the two fresh air intake holes.
  3. Check the engine cooling fan clutch for proper operation. Refer to Fan Clutch Diagnosis in the Engine Cooling sub-section of the Service Manual (SI Document ID #774320).
  4. If the vehicle is equipped with a front license plate, inspect for proper installation. If the license plate bracket is installed upside down, it will block part of the two fresh air intake holes in the bumper. When the license plate bracket is installed correctly, the writing on the back of the bracket will be upside down.
  5. Inspect for material between the radiator and condenser. Remove the top plate to confirm that there is no restriction. A radiator front filled with material will decrease condenser performance.

  6. Some improvements have been found by lowering the A/C charge from 0.82 kg (1.8 lbs) to 0.73 kg (1.6 lbs).
  7. Check the low pressure cycling switch for proper operation. The low pressure switch opens at 172-234 kPa (25-34 psi) , which stops compressor operation and closes when the low side pressure reaches 276-310 kPa (40-45 psi). This enables the compressor to turn back on.
  8. Important: Compressor clutch engagement cannot be used to determine the status of the low pressure switch. The low pressure switch is one of several inputs to the HVAC control module for A/C request authorization. A/C request is one of several inputs to the powertrain control module (PCM) that control A/C compressor clutch engagement.

    Using a scan tool to monitor low pressure switch status while monitoring the low side pressure with the ACR 2000 at the service port and watch the pressure at which the switch opens/closes is imperative to successfully diagnosing the switch.
  9. If the A/C performance has not improved after performing the above steps, replace the accumulator with P/N 89018601, using the procedure listed below. This new accumulator also requires the accumulator bracket, accumulator insulator and A/C suction hose to be replaced.

Accumulator Replacement

  1. Remove the suction hose mounting bolt from the A/C compressor.
  2. Remove the suction hose from the compressor.
  3. Remove the suction hose nut from the accumulator.
  4. Remove the suction hose from the accumulator.
  5. Remove the evaporator tube nut from the evaporator.
  6. Remove the evaporator tube from the evaporator.
  7. Disconnect the electrical connector from the A/C low pressure switch.
  8. Remove the nut from the evaporator fitting.
  9. Remove the accumulator bracket nut from the retaining stud.
  10. Remove the accumulator.
  11. Remove the retaining bracket bolt. This bolt must be reused for the new bracket.
  12. Remove the insulator. One half of the insulator must be reused.
  13. Install the new insulator and one half of the old insulator onto the new accumulator.
  14. Install the new retaining bracket and bolt to the accumulator. Do not tighten at this time.
  15. Add the PAG oil directly into the new accumulator that was removed during the recovery process plus an additional 90 ml (3 oz).
  16. Install the new accumulator.
  17. Install the accumulator bracket nut.
  18. Tighten
    Tighten the nut to 9 N·m (80 lb in).

  19. Tighten the retaining bracket bolt.
  20. Tighten
    Tighten the nut to 10 N·m (89 lb in).

  21. Install the nut to the evaporator fitting.
  22. Tighten
    Tighten the nut to 16 N·m (12 lb ft).

  23. Install the evaporator tube to the evaporator.
  24. Install the evaporator tube nut to the evaporator.
  25. Tighten
    Tighten the nut to 16 N·m (12 lb ft).

  26. Install the new suction hose to the accumulator.
  27. Install the suction hose nut to the accumulator.
  28. Tighten
    Tighten the nut to 16 N·m (12 lb ft).

  29. Connect the electrical connector to the A/C low pressure switch.
  30. Install the new suction hose to the compressor.
  31. Install the suction hose mounting bolt to the A/C compressor.
  32. Tighten
    Tighten the bolt to 16 N·m (12 lb ft).

Mark
Mark, ASE Certified Technician
Category: GM
Satisfied Customers: 847
Experience: 34+ yrs Dealership Exp. - Fully State & ASE Certified - GM Master & GM World Class Tech
Verified
Mark and 87 other GM Specialists are ready to help you
Ask your own question now
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a gm mechanicLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Mark Your Own Question
Mark
Mark
Mark, ASE Certified Technician
Category: GM
Satisfied Customers: 847
847 Satisfied Customers
Experience: 34+ yrs Dealership Exp. - Fully State & ASE Certified - GM Master & GM World Class Tech

Mark is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

I was having a terrible problem with the wheel bearings on my 98 Chevy Cavalier and I suspect that using this website saved me plenty of time and money.

Todd LRochester NY

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

< Previous | Next >

Meet the Experts:

GM Tech (Cam)

GM Tech (Cam)

GMC Mechanic

5,838 satisfied customers

GM Grand Master Technician 2007. 14 years experience.

Gary

Gary

GMC Technician

1,560 satisfied customers

15 years gm master tech/15 years ASE master tech

car tech

car tech

ASE Certified Technician

449 satisfied customers

25 year master tech and shop owner

Chris (aka- Moose)

Chris (aka- Moose)

GMC Technician

232 satisfied customers

16 years of experience

Paul M ASE Master

Paul M ASE Master

ASE Master Tech

187 satisfied customers

ASE Master Tech 20+ Years

Anthony

Anthony

GMC Technician

489 satisfied customers

GM Certified

Amedee

Amedee

GMC Technician

470 satisfied customers

ASE certified tech with advanced level specialist. Wisconsin certified emissions state inspector

< Previous | Next >

Related GM Questions
Him, the front of the truck is blowing hot air out even when
the front of the truck is blowing hot air out even when the fan is only on. When the ac is on the second and third row blows ac cold but the front vents are blowing out hot air as if the heat is on … read more
Ron Z.
Ron Z.
Vocational, Technical or Trade Scho
19,637 satisfied customers
05 gmc yukon slt. ac system functioning fine but hot water
05 gmc yukon slt. ac system functioning fine but hot water flowing through front heater core at same time rear ac works fine, front system hot air. where is heat control valve so i can check operation… read more
Gary
Gary
GMC Technician
Vocational, Technical or Trade Scho
1,560 satisfied customers
GM sierra: i have a 2006 gmc sierra 1500 pick-up with dual
i have a 2006 gmc sierra 1500 pick-up with dual temp controls. on the drivers side only my ac without warning will start putting out hot air,the pass. side is fine. if i try to correct the temp it doe… read more
Dave Nova
Dave Nova
Auto Dealership Owner
Associate Degree
8,815 satisfied customers
GM avalanche: My Ac will blow cold and then, it blows hot out
My Ac will blow cold and then, it blows hot out of the vent above the center console the facing the driver. What actuator do i need to replace? and which one is the one to buy?… read more
Dave Nova
Dave Nova
Auto Dealership Owner
Associate Degree
8,815 satisfied customers
GM Yukon: Hi I am driving a 2006 gmc Yukon. For awhile now
Hi I am driving a 2006 gmc Yukon. For awhile now the driver side air vents will blow hot for a few seconds and the. Go back to cold. Now it has gone completely hot. The passenger vents blow cold and t… read more
Gary
Gary
GMC Technician
Vocational, Technical or Trade Scho
1,560 satisfied customers
sierra: ac...heater..passenger side seems to be blowing cool air
my gmc sierra 2500hd, 8100 vortec has a problem with the ac. sometimes it just stops and the heater seems to be blowing hot air in my face. sometimes the passenger side seems to be blowing cool air wh… read more
Dave Nova
Dave Nova
Auto Dealership Owner
Associate Degree
8,815 satisfied customers
2006 Chevy Silverado 3500: drivers side..vents..the passenger side
I have a 2006 Chevy Silverado 3500. With the air conditioning on sometimes on the driver's side heat will begin blowing out of the air conditioning vents. On the passenger side there will still be coo… read more
Dave Nova
Dave Nova
Auto Dealership Owner
Associate Degree
8,815 satisfied customers
2004 Envoy: awhile..shops..ac system but must be an electrical problem
I have a 2004 Envoy. The AC has not worked for awhile. I've taken it to 2 shops & they both say it is not a problem with the AC system but must be an electrical problem. They want to do a full check o… read more
Triston
Triston
High School or GED
1,613 satisfied customers
2004 GMC: my passenger side..blowing cold..ac..driver side is fine
my passenger side of my heating is blowing cold regardless of AC or heat, driver side is fine. Any ideas? 2004 GMC Sierra… read more
Dave Nova
Dave Nova
Auto Dealership Owner
Associate Degree
8,815 satisfied customers
2005 chevrolet: my ac started blowing hot air all the sudden..actuator
My ac started blowing hot air all the sudden and the dealer is telling me that it is the actuator mode temp. How hard is this to change on a 2005 Chevolet Silverado pickup?? Where is it located? Is th… read more
Paul M ASE Master
Paul M ASE Master
ASE Master Tech
Automotive College
187 satisfied customers
2004 GMC: I just had the A/C recharged just a week..following morning
I have a 2004 GMC Denali. I just had the A/C recharged just a week ago. When I took the Denali out of the shop it ran nice and cold until the following morning. Everything blows hot. My wife says that… read more
Dave Nova
Dave Nova
Auto Dealership Owner
Associate Degree
8,815 satisfied customers
2005 yukon slt: front blower..blow cold air..the ac is charged, dave
I have a 2005 yukon slt, and my problem is the front blower blows warm air and the rear cold , and i cant make the front to blow cold air , the ac is charged, dave… read more
John
John
MASTER AUTOMOTIVE TECHNICIAN
2 YEARS COLLEGE
8,101 satisfied customers
2004 GMC Yukon: rear air..front zone blows cold and warm air
I have a 2004 GMC Yukon and the rear air does not blow warm air and the front zone blows cold and warm air at the same setting. What should I do?… read more
car tech
car tech
ASE Certified Technician
High School or GED
449 satisfied customers
2002 GMC Sonoma: SL..Occasionally..defrost to floor vent or cabin vent
I have a 2002 GMC Sonoma SL, 2.3L. When I turn my interior temperature control to heat I sometimes get warm air, and sometimes ambient air. Occasionally it will start out warm, but if I change from de… read more
John
John
MASTER AUTOMOTIVE TECHNICIAN
2 YEARS COLLEGE
8,101 satisfied customers
2002 GMC: climate control..passenger..the vent position..only blows
I have a 2002 GMC Denali XL with a front climate control problem. This particular vehicle year does not have separate driver/passenger settings. When the fan is set to Auto (left knob) and the vent po… read more
Michael Moore
Michael Moore
Team leader, bumper to bumper tech.
Associate Degree
2,870 satisfied customers
2002 Yukon: The defroster vents are blowing out cold air
I have a 2002 Yukon. The problem has happened before but it was under warranty so I do not know how they fixed it. The defroster vents are blowing out cold air. It will not switch to warm air nor will… read more
GM Tech (Cam)
GM Tech (Cam)
GMC Mechanic
Vocational, Technical or Trade Scho
5,838 satisfied customers
Drivers side ac vent blows hot air but the passenger side blows..crank
Drivers side ac vent blows hot air but the passenger side blows cold air. I have tried the procedure Anthony suggested remove the fuse and wait 30 seconds and crank the car and not touch the ac contro… read more
Wicked Wrench
Wicked Wrench
Automotive Technology Instructor
Associate Degree
458 satisfied customers
2004 chevrolet: silverado..My first problem is the recirculating door
I have a 2004 chevolet 2500 silverado. I have only had the truck about 6- weeks . My first problem is the recirculating door will not close and the air is coming in from outside. So it takes a long ti… read more
Jerry
Jerry
Service consultant
Vocational, Technical or Trade Scho
13,107 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x