someotherguy
Truly Awesome
What everyone should keep in mind when responding is OP has a '90 Suburban which is a squarebody, so any part #'s for a GMT400 are not likely to cross over.
Also control-specific comments are likely to be less relevant, too. Squarebodies still rely on cable/lever and vacuum style controls. It may be a door operation issue, or the evaporator core may be clogged with debris still. Depends on where all you've cleaned. It's been forever since I've messed with any squarebody and the evaporator housing is very different from a GMT400, but I'm sure they can get clogged up just the same. There are spray foam cleaners meant for this job that you can shoot in there but specifics on getting it in there for your generation of truck, you may want to do some searching on youtube or otherwise. Cleaning leaves/pine straw/etc. out of the box is a good start but the evaporator fins are likely covered in "mud" from years of dusty air combining with evap moisture, and this will impede airflow considerably.
Just for reference, pic is from a GMT400 evap housing, but an example of just how funky an evap can be and this is from a truck where the A/C was actually working reasonably well with decent airflow. I took it apart anyway because I was swapping this housing into another cab. Glad I did the extra work. This is from a '98 model that I took apart in '09 so only 10-11 years old at the time.
Here's one from an older parts truck from years before...nevermind the loose debris, it's the mud that is the real airflow-killer.
Richard
Also control-specific comments are likely to be less relevant, too. Squarebodies still rely on cable/lever and vacuum style controls. It may be a door operation issue, or the evaporator core may be clogged with debris still. Depends on where all you've cleaned. It's been forever since I've messed with any squarebody and the evaporator housing is very different from a GMT400, but I'm sure they can get clogged up just the same. There are spray foam cleaners meant for this job that you can shoot in there but specifics on getting it in there for your generation of truck, you may want to do some searching on youtube or otherwise. Cleaning leaves/pine straw/etc. out of the box is a good start but the evaporator fins are likely covered in "mud" from years of dusty air combining with evap moisture, and this will impede airflow considerably.
Just for reference, pic is from a GMT400 evap housing, but an example of just how funky an evap can be and this is from a truck where the A/C was actually working reasonably well with decent airflow. I took it apart anyway because I was swapping this housing into another cab. Glad I did the extra work. This is from a '98 model that I took apart in '09 so only 10-11 years old at the time.
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Here's one from an older parts truck from years before...nevermind the loose debris, it's the mud that is the real airflow-killer.
You must be registered for see images attach
Richard
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