first off, is the engine developing heat? Does the temp guage rise in a resonable amount of time? It should since you fixed the thermostat.
now, if your engine is at proper running tempterature and you don't feel heat there are two things to look at next:
(1) Is your fan working?Even if it isn't working, you should still be able to feel some heat when you are traveling at a good speed since air will be coming through the grill.
(2) More likely your heater control valve is broken or the wire connecting the switch on the dash and the valve has broken. I had the wire break on my 02. To isolate the problem, go inside the engine bay and if you can get access to it, manually turn the heater valve. If the cable is broken this will allow you to turn your heat on. If you still have no heat, then either your valve is broken or you need to look further into the situation.
Check for fluid leaking (coolant) into the cabin. If the heater core is cracked it will leak fluid into the cabin when the heater vavle is open. This is unlikely because you would have noticed your radiator fluid dropping and your carpet getting wet.
Lastly, depending on the quality of the swap, there is a chance the heater was never hoooked back up. Someone might have botched the job and taken the heater out of the cooling system loop to save time and effort. This is easy to see, just look at the back of the engine bay and make sure there is a cooling hose running from the engine block or head to the firewall area. The heater core should be located behind the dash, so a hose running behind there is a good sign.
Hope this helps out some. Get back to us on your results.
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1970 - 2002
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