So, I had my 1988 e150 in the shop recently for some routing engine work and new gaskets. After I got the vehicle back, the Climate Control selector doesn't appear to work (much less trigger the AC condenser).

The fan still blows just fine and the mechanical damper is working, but the output of the unit is stuck in "defrost" (towards the windshield) which is where it was the morning I dropped it off for service.

What could cause this symptom? Fuses look fine. Is there a vaccumn line going to the Climate control that could be missing?

Dan

 

Yup. An air discharge from the defrost ducts regardless of selector setting is nearly a sure sign of a vacuum hose knocked off.

 

Where might I look under the hood/doghouse to confirm this? My mechanic is a bit of a drive, and I'd hate to have to drive all the way there to be wrong... I DO want them to fix it right if it wasn't done properly (they're on my bad-list already).

Dan

 

The relevent vacuum line is the only one that feeds through the firewall. You'll have to look around to find it

Once identified, inspect it for proper connection, cracks, or other breaches.

The wrench might have knocked it loose or may have cracked while doing the other work. They're plastic and can get very brittle after that many years.

Steve

 

I assume that connects to the main vacumn tree on the intake manifold (as opposed to a solenoid somwhere...)?

Dan