my o7 chevy colorado loosing coolent.I added 16oz. 50/50 to it.2 weeks later about 8oz gone.2 dealerships pressure tested it-no leaks.Don’t see any in oil.Any ideas?
Intake manifold gasket leak?
Either would allow coolant to be ingected into the cylinders and blown out as vapor.
just had a upper and lower intake and manifold done on a chevy.most of the cost was labor.
I can’t imagine that is wasn’t sorted out by '07 but GM 6 cyl engines (don’t know if yours is 6 or 8, but it might not matter) have had widespread problems with intake manifold gaskets.
Look for signs of coolant in your oil and get it sorted out asap before it does engine damage.