1995 Pontiac Grand Am STILL NO HEAT

If I understand you, you get volume of air from the vents but it is cold. Right?

If so, when the engine is hot, how hot are the hoses going into the heater core and coming out of the heater core? How hot is the radiator hose going into the radiator and coming out of the radiator? Also both hot? Or not?

Is the coolant mixture about 50/50? Where is the temp gauge reading? Is the coolant full? Did you bleed the air out of the system?

The thermostat shouldn't open until 195 degrees, I believe on that one. The engine wants to hog the heat until it is warmed up, then it lets you have some.
That coupled with the heater hoses not being very hot points to the t-stat to me. It is not uncommon to get a defective part that is new. If the system wasn't bled, it would create a hotter situation, not colder. Bobby71 did give you important info regardless. IS don't see it as the fix, but it's quick enough to do. :)

:oops: For a service writer you think I would communicate better :)

I don't think bleeding the system is going to help you now. I would expect the engine to run hot if it needed bleeding. I was being respectful to bobby71 in the event that you bled the system and you got heat.

The theromostat remains closed until the car reaches 195 degrees. The coolant essentially only circulates throughout the motor until it is hot enough to relax a rich fuel mixture. When the stat opens, it will circulate into the heater core and the passenger compartment gets heat.

If the thermostat remains open when it is less than 195 degress, the cold coolant will circulate throughout the system and take a long time to get to temperature, this giving you lousy heat or none.

I am suspicious of a fualty new t-stat.
Sorry for the confusion!

How long do you let the car run and still get no heat when at idle?

I don't want to send you down the wrong path. After 45 min, it should have some sign of heat, as in the t-stat is probably ok. My knowledge gets thin in some areas and I'm reaching that point on this. I need to do a little research to go further. Control unit in the dash malfunctioning?

Maybe one of the others here can take over, If not I can get back to this tues or wed.

Anyone?

IF the t-stat replacement did nothing, try backflushing the heater core.

Disconnect the heater core lines, Using a garden hose and not real strong pressure, run water through the heater core in the reverse direction. Alternate the flow a few times as well. You want to be looking for anything to be coming out of the core and for good flow.

There has to be a direct short. Try unplugging the blower motor fan and see if it continues to happen. If it does, it's time to start tracing wires to see where the short is located. If it doesn't happen, check to make sure the plug is in good condition. If so, replace the blower motor.