Question about 1999 Chevrolet Astro

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Minimal heat coming out of defrost, more than vac problem?

Hey my name is Carl from toronto. I have a 1999 astro van and the heat only comes out a small bit out of the defrost on the dash, i have already replaced the blower motor. After looking up the problem online it seems that the vacuum lines needs to be replaced for the dial to work. If this is changed will it create more pressure coming out of the ducts?

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The vacuum line you're looking for is in front of the throttle body. It runs from the top of the pvc valve on the drivers side of the engine and crosses in front of the throttle body down to the tee near the a/c accumulator. When you replace the hose use a piece of wire loom to cover the hose so that the engine heat will not break it again.

Posted on Oct 06, 2009

Testimonial: "thanks very much for the feedback, I understand this is probably the problem but if the vacuum line as changed will that increase the pressureoftheair"


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