I'm at the end of a TPI swap into a 1993 Caprice wagon.. It's actually running!

This morning there was some condensation on the windshield so I flipped the defroster on, and the fan on high. I got lots of air moving around but no heat. So electrically The fan motor is working OK, but no heat came through.

I can appreciate why I woulnd't get A/C happening as this point as the relays haven't been pinned into the ECM as of yet.

I noticed on third gen cars there is what appears to be a manually controlled valve coming off the trottle body ( passenger side) I don't have this on my car, but figured without out it ,I'd ALWAYS have the heat on, not no heat.

I thought the water flow should see a cycle from throttle body to heater core back to radiator to radiator. Maybe I was misunderstanding the path of the coolant? What did I do wrong?

What should I be checking (and how do I check it) to make sure I have water flow, correctly plumbed, etc. I assume vacuum comes into this picture somehow since there is a vacuum valve ob the controls!

Thanks for for responses, Dave.