Hi Scotty! I have a 2002 Chevy Avalanche 1500 that runs great but when I drive it with the AC on I get a "Low coolant" light and notice a loss in coolant in the reservoir, what could be the cause?
Thanks
Clarification: Mileage?
Around 140,000 miles
Maybe the surge tank cap leaks pressure when the cooling system pressure increases when the AC is on. Try replacing the cap
Thanks for the suggestion, I will try replacing the cap.
You're either leaking it or burning it in the engine.
Thanks for your response. If it was buring in the engine though wouldn't it be buring regardless if the AC turned on or not?
The engine is under more strain and may run a bit hotter when the AC is on.
Leaking or burning are the only causes of coolant loss. You need to do some diagnostic work to find where the coolant is going.
If it's leaking, find and fix the leak. If it's burning, you need a new head gasket. Get a leak test kit at the auto parts store and pull your spark plugs and see if any are wet with coolant.
