Having problems with your 1997 Chevrolet Venture ?
My heater blows warm air when fan on low then when you turn the fan on high it gets cold.
This indicates that enough hot water isn't getting from the engine into the heater core at a fast enough pace to keep up with the increased demand when you have the fan on higher speeds, and that the system is restricted. If your temperature gauge is indicating the engine is at normal operating temp. or you can tell by the general temperature of the engine, then more than likely, you'll need to have the entire system cooling system tested & flushed good luck
Repair Help & Product Troubleshooting for 1997 Chevrolet Venture
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