QuestionMy question is related to one you answered recently regarding an air conditioning problem. I have a 2002 GMC Denali XL that is having air conditioning woes. To be more specific, the belt is slipping during acceleration. I have had the tensioning arm replaced as well as the belt. Previously, I've also had the computer reprogrammed but the problem still exists.
My brother in law was also GM master certified some years ago but has not worked at a dealership in several years (since 1997) and, based on discussions he's had with other mechanics, thinks it may still be related to the computer software. My question is this: was there a new load of software developed to reprogram the computer to address this problem. In fact, he told me of a story where one of his mechanic friends replaced the belt, arm and compressor only to find the problem still existed. He ultimately purchased the equipment necessary to "flash" the computer and finally resolved the problem (at an expense of 6K)only after replacing the compressor twice.
I know this is a lot of information but wanted to get your thoughts as I'm not excited about having the compressor replaced only to find the problem still exists. Know it's a lengthy description but wanted to give you the full story.
HELP PLEASE....
Thanks!
AnswerHi
I checked ALL bulletins and PI's for youe\r vehicle and year before and year after.
The ONLY reflash I see is a reflash for the HVAC controller for the mode doors home/homing properly.
There is NO PCM updates and no other HVAC updates.
Here is the bulletin # for the Slugging
03-01-38-019A
Here is the ENTIRE bulletin.
Be advised, the in line filters are NOT AVALIBLE from GM anymore, at least from my dealership.
I Hope this helps.
This bulletin is being revised to update the service procedure and parts information. Please discard Corporate Bulletin Number 03-01-38-019 (Section 01 -- HVAC).
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Condition
Some customers may comment about an underhood rattle noise heard on acceleration or a sudden loss of A/C system performance.
Cause
This condition may be caused by liquid slugging of the A/C compressor. This condition may cause an internal failure in the A/C compressor. The serpentine belt tensioner and serpentine belt may also be damaged.
Correction
Technicians are to check the A/C system performance and compressor operation using the following repair procedure:
Open the hood and inspect the A/C compressor for damage and to see if the compressor is seized. Verify that the serpentine belt is not damaged or missing. If the A/C compressor is seized, proceed to step 5.
Perform the A/C System Performance test. Refer to the Heating, Ventilation and Air Conditioning (HVAC) section of SI. Correct any performance concerns or refrigerant leaks that are found.
Inspect the vehicle for other possible sources of A/C compressor noise or performance concerns. Refer to Corporate Bulletin Number 01-01-38-013 for more information.
After all other possible sources of A/C compressor noise or performance concerns have been eliminated, only then should the A/C compressor be replaced.
Remove the A/C compressor. Refer to the A/C Compressor Replacement procedure in the HVAC section of SI.
Inspect the transmission cooler lines for damage due to contact from the serpentine belt. Replace the transmission cooler lines if necessary.
Install an inline A/C system filter. Refer to Corporate Bulletin Number 01-01-38-006C for more information about A/C system flushing and filter installation procedures. An A/C system flush is not to be done unless prior authorization is given by the GM Area Service Manager (in Canada, the District Service Manager).
Install an A/C Suction Screen. Refer to Corporate Bulletin Number 01-01-39-003A for more information about A/C suction screen repair recommendations and procedures.
Install a new A/C compressor. Refer to the Compressor Replacement procedure in the HVAC section of SI.
Install a new orifice tube for the front A/C system. Refer to the Expansion (Orifice) Tube Replacement procedure in SI.
If the vehicle is a 2003 model year Chevrolet Express or GMC Savana van, the vehicle may require a new accumulator. Refer to Corporate Bulletin Number 03-01-38-016 for more information. This bulletin refers to an updated design accumulator that may improve the performance of the A/C system.
Install a new serpentine belt tensioner and serpentine belt if they have been damaged due to A/C system slugging or an A/C compressor seizure. The serpentine belt tensioner may have broken stop tabs and/or a missing front cap.
Verify proper operation of the A/C system.
Parts Information
Refer to the GMSPO parts catalog for the latest service replacement compressor part numbers.
Part Number
Description
Qty
89016656 (*A/C Delco Part# 15-10413)
Universal In-Line A/C Filter
1
Parts are currently available from GMSPO.
*This filter may also be purchased through your local A/C Delco distributor.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
D4440
Compressor Assembly - Replace
Use published labor operation time
Good luck
PAwl
