GMC Troubleshooting Questions? Ask a Mechanic for Answers
The engine coolant has a few places it can go, and all but one can be ruled out easy. Into the transmission, engine oil and onto the ground. If its none of those then it has to be getting into the combustion chamber to be burnt off with the fuel and pushed out the exhaust. It takes alot of coolant loss into a cylinder to cause a misfire and smoke. A cylinder compression test is needed if the first 3 leak possibilities show no issues.
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