DonnyO

2002 GMC Savana

Only had this a couple of months and I knew the A/C was INOP. The previous owner cut the hoses going to the rear A/C underneath about half way back and eliminated the rear A/C altogether. I found this out when trying to charge it.

I got the two hoses for a non rear A/C van, did a proper service, evacuated, added oil and charged it up. The far right vent is blowing out 58 degrees at 95 outside temp so the system is working properly. All modes, defrost, panel vents and floor all respond normally. Blend door actuator is working and temp does change to hot and cold but the panel vents are always ambient temp, except for the far right vent. I removed the blend door actuator and the door feels normal with no binding and I can hear it close when manipulated by hand. All the vacuum actuators also operate and hold vacuum and respond as designed according to my Mitchell service manual.

I am a retired auto tech of 40 years and I've repaired a couple hundred A/C systems. The charge is correct and gauge readings are within specs. The only thing I can think of it the mix doors that switch for the IP panel vents are broken or not sealing but I have never been inside the heater/A/C case on one of these and it looks like a royal bitch to get this thing apart.

Have anyone ever come across this problem?

mountainmanjoe

I have taken apart the air ducting for the rear system. and I notice the plastic distorts and collapses quite a bit (heat cycling?) leaving massive gaps between sections. The foam that seals the joints just turns to dust after a while. The duct sections are very loosely mounted with plastic clips which also get brittle and break, leaving them to hang or fall out of place. You can see that quality was job none for GM. You may be facing similar issues. Could need a dash-out overhaul. I know , I know ... when they build these things they start with the HVAC systems, and then assemble everything around it.