Hi I have a 1994 jimmy with a w vin. There seems to be a sound coming from the engine. It sounds like an accordion coming from the globe box area. Also my heater just started only working on defroster and nothing else. Anyone have any ideas?

 

A loss of vacuum to the HVAC controls will result in the HVAC system going to default positions which happens to be defrost.

 

Where are the vac lines located?

 

They run from the engine, through a check valve, to the vacuum reservoir under the hood, then through the firewall and to the HVAC control module. If you have 4wd, there will also be a 'T' after the check valve to go to the transfer case.

 

Those are the lines that come off the back of the intake manifold correct? The ones just above the distributor?

 

yes ,and the resevoir is that black sphere about the size of a 5pin bowling ball.

 

One of my Vac lines came off so I zap strapped it in place so wont pop off again but I still hear a weird noise coming from behind glove box. I think maybe my blower motor is on its way out. The sound sounds like an accordion.

 

ttt please

 

Please wait at least 24 hours before bumping your post. Consecutive posting outside of that guideline is against forum rules.

Could you describe the noise in more detail? Have you investigated under the dash to find the source of the noise? If not, it might be a good idea. You could have been doing something constructive instead of uselessly bumping your post at 2AM EST.

 

HAHAHAHA Sorry boss but I live in the west and it was 11 pm when I posted that. My bad anyways back to my Jimmy

When I accelerate there is a noise that sounds like an accordion/air groaning coming from behind the glove box/floor area. It rises with the rpm of the engine and when the trans shifts to the next gear it goes away until the rpm rises again. I had the trans rebuilt less than 3000km ago so I know its not that. Any help boys?