06 LaCrosse no heat

[WalleyeChaser]

I have a friend with a no heat problem. Changed out the thermostat but didn't help. Thinking it is something with the heater core. Circulation issue? One heater hose will be hot while the other is barley warm. Or is it something with the digital controller?

[Jeremy airjer W]

3.8?

did you check the coolant level before changing the t-stat?

are you sure you purged the cooling system completely?

What was the condition of the coolant?

Was there a check engine light on with a code for low coolant temperature?

Are you sure the coolant elbows that go into the tensioner are not leaking (3.8 liter)?

[WalleyeChaser]

Yes it has the 3.8. I have a 97 park ave that had the coolant elbow leak so that's the first thing I checked. Everything else you mentioned was checked/ no leaks, no codes, system full, no air spits out of bleeder on thermostat housing. Is there a bleeder somewhere els? It seems that it is not switching or opening something on the blower assembly to allow the hot air to be blowen into the car. Just barley warm is all I can get. A/c works fine. I am a body man and know some light mech. but this has me baffled!

[Jeremy airjer W]

With the key on, the engine off, the blower set to medium or high, turn the heat nob from full cold to full hot. can you hear the air flow change as the blend door moves through it range?

The heater hoses are pretty easy to get to and it wouldn't be that hard to back flush the heater core as an option.

[clownshack]

Wife had the same problem, same car, same year. I thought blend doors, or climate control electronics. The issue was intermittent, I flushed the junk dex-cool out and replaced with Green antifreeze. Works good now. The coolant looked real bad when flushed, I think a quick lube added incompatible fluid or she has a manifold or head leak starting.

[Jeremy airjer W]

thats pretty normal for the dexcool

[redtrucks]

My daughters 06 Grand Prix had the same issue. Changed the thermostat and bled the air out of the system, still no heat. Back flushed the heater core and now it can cook her out of the car.