HVAC Air Movement Issue
terryshrout
10-05-2009, 09:50 PM
just replaced ignition switch, blower motor and resistor on 01 GP. During work I disconnected 2 vaccum lines from a black triangular tank under dash directly below manual HVAC conrols. Heard air escaping from tank. Just hooked up battery and tested HVAC activity. Blower motor and AC works on all speeds now but air only comes out of dash vents, not floor or defrost, regardless of control position. Will starting car and building up air/vaccum solve this issue or do I need to be looking elseware or doing some other process? Like always, thanks in advance for help.
tblake
10-06-2009, 10:21 AM
Coud the thing you disconnected be some sort of a one way check valve where the vacuum lines can only be connected on the right spots and possibly its backwards?
Otherwise take a look and make sure none of them weren't cracked by mistake.
Otherwise take a look and make sure none of them weren't cracked by mistake.
richtazz
10-06-2009, 10:23 AM
Starting the car and letting it idle should resolve your issue. The tank you disconnected is vacuum storage for the HVAC system so it continues to work even during
hard acceleration when engine vacuum is low.
hard acceleration when engine vacuum is low.
terryshrout
10-06-2009, 10:39 AM
thanks guys. Will run car tonight and see if vaccum problem resolves it's self. Will update then
terryshrout
10-16-2009, 07:43 PM
Thanks richtazz, starting car and letting it run a few minutes built up vaccum in canister and cured the problem. You guys saved me lots of money
richtazz
10-17-2009, 02:43 PM
You're very welcome, glad we could help out, and thanks for the feedback. We like hearing the happy endings.
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