I swapped in a 'fresh' D16Z6 after a spun a journal in my old one.

Since I swapped the engine in it will start very boggy for 5-10 seconds and then run like a champ from then on. This doesn't always happen. Just sometimes.

A couple of days ago the engine began heating up above the halfway point. I immediately rolled down the windows and cranked the heat. Bare in mind it was 35 degrees F outside. That helped so that I could limp home. Then today, I drive it to the place where I work on the car and it was slow to heat up. It wasn't until I got all the way there (20 minute drive) that the engine finally was up to temperature.

As soon as I pulled in the driveway it just started to heat up above halfway again. So, I was thinking maybe some junk is clogging the coolant from flowing, idk. I have had a thermostat fail shut on me before so I was thinking that the thermo was dying too possibly. I go to relieve the pressure in the coolant system by removing the radiator cap only to see that there was no coolant in the top of the radiator.

I topped it off, thinking that for some stupid reason coolant never got into the heat core and that that was the reason the coolant was low. Now the engine with NOT heat up at all. So, I'm thinking the thermo failed open (like it's supposed to) but I seem to be loosing coolant yet. wtf? Does this sound like the head gasket just crapped out on me? Since it's so cold I can't tell if the exhaust is white smoke or if it's just flippin' cold outside.

From here I plan on replacing the thermo and monitoring it. What else should I be doing?

Thanks!

 

check your oil to see if its milky

 

Do a compression test and a leak-down test. That'll let you know if it's your head gaskets or not. I'd think if it was your head gaskets, you'd be smelling the burning coolant by now.

Did you check your radiator to make sure there's no pinhole leaks anywhere? And yes, a failed thermostat would cause the car to overheat, but air in the cooling system will make it happen a lot faster lol