Me1960dude

I have a 1990 Cavalier. I have had the radiator rodded out. new thermostat, new radiator cap, and a new heater core installed. I still have cold air coming out.

Any help? I don't know anything else about the cooling/heat system. Is there something that allows water to flow between the outlet and intake of the heater core? I have disconnected everything individually and water seems to flow.

brucedana

Try Checking the heater control dial in the dash.If that dial is bad it won't open and close the vent for hot and cold air.

dwalmop

brucedana has a good point. Also make sure there is no air in coolant system. You replaced a lot of things and if it's not bled correctly, there's a good chance you'd get no heat.

hupkwondo

Seems to me the first thing to do is see if coolant is flowing into the heater core. I had the same problem on my old Subaru and it turned out the heater bypass hose was pinched not allowing coolant to flow to the core. Easiest way to test is let the car run until it gets warm, then feel the hoses going to the core (after shutting off the engine, of course). There should be two hoses and if neither is warm, look for a pinched or clogged hose in the engine compartment. If one is warm and the other cold, either the (new) core is clogged or the heater control valve is stuck. If they're both about the same warm temperature, heat is getting to the core, but air isn't flowing around the core, look for a vacuum hose that's off which controls the damper door.

Hope this helps.

Greg