Question about 1987 Chevrolet G20

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I cant switch my defrost to vent or heat - 1987 Chevrolet G20

Posted by Anonymous on


5 Suggested Answers

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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: we`re getting heat blowing out the heater vents

Hello Ruckus.
There is a vacuum controlled actuator on the heater box to the right of the drivers foot.
You may need to remove a hush panel to see it.
The vacuum line may be cracked or broken to this.
Or the mechanical connection to the door may have fallen off.
If it appears to be intact check for vacuum at the line when you move the control.
Here is a diagram to help you locate it. The actuators are on the left side of the diagram.


Thank you for using FixYa.


Posted on Nov 20, 2010

  • 1949 Answers

SOURCE: My heater control will not

blend door motor on heater box needs replace or at least checked

Posted on Nov 27, 2010

  • 227 Answers

SOURCE: Heat only blows out of defroster vent and dash

ck bleed door to make shore it working or vac hose going in to dash from out side

Posted on Feb 02, 2011

  • 44 Answers

SOURCE: 2004 silverado ac vent switch

Vac. Leak check under hood & behind dash vac.hose smaller than a pencil

Posted on Jul 23, 2012

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Window defrost

it all has to do with vacums basically, when you turn the switch to defrost there is a hose that should **** a "door" so to speak over lettin the air travel through your defrost vents, and if your not gettin suction the in aint gonna switch over, and are you gettin it out of the floor vents?

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