Question about 2005 Pontiac Grand Prix

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I want to flush the heater core

Of an '05 Pontiac grand prix. I can see the hoses that run into the firewall and attach to the engine with spring clips. I don't want to replace the heater core, just flush it. I was told that that might solve my problem of only lukewarm heat coming through the vents even when I have the temp knob all the way to HOT.

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  • byron_keaton Dec 24, 2008

    Thanks a bunch E. It seems though, that it would be a lot easier to remove the hoses at the engine. Is there a reason that I should not do this?



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Take off the hoses at the bulkhead/firewall that go to te heater core, use a garden hose and back flush the core by forcing water through the smaller of the 2 hose nipples, if the water runs right through then you have a heater air temp control door actuator problem

Posted on Dec 24, 2008


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