Heater core replacement

Also check if it has a heater control valve

They do not use a valve in this system and blend system was used
as they direct the air thro and over the heater core and or the AC system and fresh air

heater core need to be isolated and flushed

If water running thru freely and no heat on the inside, engine reaching operating temp,
check blend door operation and I would suspect the actuator on the door

Under the dash on the heater box
i will try to find a picture for you

This a picture of the part and what it look like
let me know

Good luck
let me know

Hi Trafficflow,

Thank you for the donation.

Note the cable position at valve at fully opened and fully closed position.
Disconnect the cable and check the valve operations manually.

Operate the valve manually and compare the fully opened and closed position. If there are any difference, readjust the cable and retest.

If no difference, fullly open the valve and with engine running, compare the heat of both hoses, they should be similar if coolant is flowing through.

Did you recheck the coolant level after the thermostat replacement? Any air trapped in system can cause the heater to work erratically.

Another possible cause would be the air mix door.

To test if the heater core is clogged, disconnect both hoses and use a water hose to flush through. If water flows freely, it should be good.

I am unable to find any clear diagrams for the heater valve and other items from our database. The heater valve should be in engine compartment near the heater core hoses.

Just before we proceed further, I would like to know the following.

What is the actual problem that your are facing? No heat with blowers functioning correctly?

Are all the various vents selection working correctly?

The vents and air mix are activated by vacumn and if they are not functioning correctly, it could be a clogged or leaking vacumn line.

As the vents are working correctly, the issue shoudl not be from the vacumn.

Check the heater hose and valve near the firewall.