CrimsonRacing

1994 LT1 Coupe

after installing a brand new optispark dizzy,harness and ecm,now the heat is not working(which did before).......ideas?


any input would be appreciated

Silver96ce

When you say the "heat is not working" do you mean the HVAC system is blowing cold air? If so, check and make sure that you have gotten all air out of the system and that the hoses are attached to the correct locations. If the system is not turning on, check the fuses.

CrimsonRacing

Silver,
Yes....it is only blowing cold air sir.

1993C4LT1

Maybe a dumb question, but did you let the car warm up? Are all vacuum lines connected?

CrimsonRacing

car ran to operating temp......hoses are good and warm....only cold air coming thru vents....appears all vac lines are connected but I am thinking one might have been missed.

auggy

Is the car running hot or overheating?

CrimsonRacing

car is showing normal operating temperature.....

Cliff Harris

Are the heater hoses going into the firewall both hot?

There is a restrictor in one of the heater hoses. Sometimes trash builds up there and prevents the coolant from flowing through the heater core.

desertmike1

Warm is not good enough!

They should be Hot to a point that you can't leave your hand on them.

If their Warm then there is a restriction in the lines themselves or the heater core.

I would try a simple Heater Core back flush with a garden hose. This as helped many of us in the past.