This isn't about asking for help but rather a solution to a problem I had.

A few other threads mentioned the problem with the engine cooling system. The engine would warm up but not reach proper operating temperature and yet still blow hot air out of the heater vents.

The problem was a thermostat that was stuck partially open. The engine would only warm up to 158 degrees according to the scan tool I plugged in and not get any warmer unless it was a real hot day with the A/C running. Since the engine wasn't overheating, I didn't think it was a problem. It had always been like this since I bought it a few years ago.

Simple way to check is to jack up the right front (passenger side), take the radiator cap off and remove some anti-freeze and put in the overflow tank (or whatever) until you can see about 4-5 tubes. Start the vehicle and observe the tubes that are in the radiator. There shouldn't be any coolant coming through at all. I did this and observed some coolant being circulated through the radiator. It didn't appear to be much but it was still circulating before the thermostat was supposed to open. Since it passenger side was elevated and water doesn't flow uphill, I knew it was under pressure.

If the coolant cannot remain in the engine block, it won't warm up to temperature as it is supposed to.

I replaced the thermostat with a new one and it reaches proper operating temperature as it was designed to do.

 

Thanks for sharing. These "solved" or final-report posts are very useful and helpful. Glad you figured it out!