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grinch4om · 11-11-2008, 06:41 AM

check your vacuum canister, there should be a one way vacuum valve in line with the canister, my bet is this valve is missing or non functioning

11-11-2008, 06:41 AM	#2
grinch4om dang its hot Join Date: Nov 2006 Location: frankfort kentucky Posts: 1,349	Re: Heater Box Vacuum Source??? check your vacuum canister, there should be a one way vacuum valve in line with the canister, my bet is this valve is missing or non functioning