| slymer |
Jul 7, 2009 04:58 PM |
you probably have a vacuum leak somewhere or a broken check valve. Unfortunately, there's a lot of stuff to check for this one. the main one is the PCV valve. if it's never been changed, that's going to be a major contributor to your problem. replace it. if it's been replaced recently, don't worry about that one. check all the vacuum lines you can find for cracks/breaks, disconnection. replace the ones that are broken. check valves should allow airflow one way, but not the other. If they allow air to flow both ways, replace 'em. The warm air is probably due to the heater bypass valve on the heater hose not being pulled shut due to the low vacuum pressure and allowing hot coolant into the heater core which will warm the air. This can also be caused by the transmission not downshifting when it should and lugging the engine. This can also be caused by the engine not running well and lugging when it should have plenty of power to spare. weak spark and low compression can contribute to this. Usually it's the vacuum lines though.
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