[SbcToLs1]

Ac works fine. But when you put it to hot it feels a little warm for about two seconds. Then it blows whatever the outside temp is. The heater core inlet and outlet seem to be hot and the same temp. What's next to check before I waste a whole weekend?

 

[Charlie Nichols]

One of the the cables/doors/actuators in the duct work is phucked up?

/off chance that the heater core is plugged up inside?

 

[Bigtruckdrivah]

Dafuq you need heat for in July?!

 

[Nova Dan]

Can you hear the diverter switching?

 

[BigRicky3]

It's probably the controller itself. The dash knob peice.

 

[Life's a Drag]

Consider yourself lucky, usually it's the A/C that's shot.

 

[JoDon]

Dafuq you need heat for in July?!

He's in Minnesota .... it's still winter there.

How much do you want to bet that there is already a recall notice about the problem. It is a GM after all. :smt044:smt044:smt044

 

[njk4o5]

blow hose water through the heater core, should clean it out

 

[texasoutlaw89]

It's probably the controller itself. The dash knob peice.

This

blow hose water through the heater core, should clean it out

Then this

Dafuq you need heat for in July?!

And also this

 

[Mcgyver]

Dumb question, but I gotta ask...is the cooling system full? The heater core is the sometimes highest point in the cooling system, and I've had customers with same complaint that didn't realize the coolant was a little low.... but I'm sure that was the first thing you checked.

 

[SbcToLs1]

All that I've confirmed so far is the inlet and the outlet on the heater core are the same temp. Hot.

 

[Dan Osborne]

Electric actuator on the temp door. There are three of them behind the ashtray area. I had to replace the one on my 99 Tahoe that changes defrost, vents, floor. When I pulled it and changes the settings you could see it try to move which told me the control was sending the low voltage. You can get them at parts store but I unscrewed mine and did it manually first. Parts store guy said they go bad all the time.

 

[SbcToLs1]

I'll dig into it tomorrow after work.

 

[dave89iroc]

Electric actuator on the temp door. There are three of them behind the ashtray area. I had to replace the one on my 99 Tahoe that changes defrost, vents, floor. When I pulled it and changes the settings you could see it try to move which told me the control was sending the low voltage. You can get them at parts store but I unscrewed mine and did it manually first. Parts store guy said they go bad all the time.

yup, the blend door actuator, I had to replace it on my 2000 silverado

 

[SbcToLs1]

Fixed it yesterday. Plugged heater core. Still have the damn red dexcool in it from the factory.

 

[ISELLSPEED]

Nothing like taking your time on a repair......lol

 

[Russco]

Electric actuator on the temp door. There are three of them behind the ashtray area. I had to replace the one on my 99 Tahoe that changes defrost, vents, floor. When I pulled it and changes the settings you could see it try to move which told me the control was sending the low voltage. You can get them at parts store but I unscrewed mine and did it manually first. Parts store guy said they go bad all the time.

This I've changed a few of them in the past too.

 

[SbcToLs1]

Nothing like taking your time on a repair......lol

Didn't even touch it until the other day. Ain't got time for that shit.