Coolant system antics

[Effduration]

Originally Posted by Oldmactech

I’m going under it tomorrow to look for leaks, is it odd that the coolant hoses are tight after sitting overnight?

If hoses are still tight (hard with pressure) after sitting overnight, that is a sign that exhaust gasses are entering the cooling system...

Originally Posted by Oldmactech

Brief follow-up, looks like the electric fan is not functioning- comes on with AC right? And the cold start valve connecting hose was a bit cockeyed- maybe enough to create a stumble?

Yes Aux fan should come on with AC..It may also come one when you unplug the coolant temp sensor in lower radiator hose. It also flickers on at every start-up .

In my case both aux fan and clutch fan had failed, I didn't notice it (no error codes) and the car overheated in traffic while a family member was driving it.