No Heat.

[T What?]

Heater would sweat you out last week Friday. Got in the car on Saturday morning and no heat at all. No smell of antifreeze, fan working fine. What do I do to diagnose if its the heater core or any other issue. Thanks for the help Gents.
Dustin

 

[jlat]

hello; I'd say the thermostat is stuck open. If it was stuck closed you'd over heat and there's a safety feature in the stat that won't let that happen. I'd just change the stat.
I see your from florida. How cold was it been lately? Here in Mass. it's been unseasonable but last night it was in the 30's where I'm at.
IBBY

 

[Phoneguy]

Either the heater control valve isn't working or the cable at the dash control isn't moving. Try moving the heater valve by hand to see if that helps. You can also bypass the valve and have full time heat if that is the problem.

Bryan

 

[jlat]

hello; Funny you say that about by passing the HCV as I heard if you remove it the heat will be better. I did that on my van and the heat is about the same and my next move is to flush the heater core and see what happens.
IBBY

 

[T What?]

well I hope its not the thermostat, I just put a new billet 160 in may along with a flush. I appreciate the info. It has been in the low 30's here in the morning.

 

[jlat]

hello; There's a bunch of things it could be and I see you have a handle on that. Could you post when you get it fixed.
thanks
IBBY

 

[Phoneguy]

hello; Funny you say that about by passing the HCV as I heard if you remove it the heat will be better. I did that on my van and the heat is about the same and my next move is to flush the heater core and see what happens.
IBBY

I can't see the heat being any better than a properly functioning control valve. What would the reasoning be?

Bryan

 

[big dre]

I'm having the same problem but i do not smell antifreeze. Mech said it was the heater core so should i change to a new HCV since I'm changing the heater core out?? Thermostat is a 160 degree and new and reading correct as far as the scanmaster #'s.

 

[Phoneguy]

I'm having the same problem but i do not smell antifreeze. Mech said it was the heater core so should i change to a new HCV since I'm changing the heater core out?? Thermostat is a 160 degree and new and reading correct as far as the scanmaster #'s.

Bypass the control valve before you spend time and money doing a heater core. Then check to see if the cable is moving at the dash control. Troubleshoot before replacing parts...

Bryan

 

[BobbyBuick]

If it was the core your floors would be wet and or your windows would be fogged up
First check the coolant level if low no heat
Second check the hcv with a mighty vac and make sure the line hooked to it is pulling a vacuum
Third open the glove box door and look at the plastic L shaped lever that is hooked to the heat lever and see if it is broken and or functioning

 

[Buickforlife]

Feel the heater hoses going to the heater core. They should both be hot if you find that one is cold and one is hot you have a clogged core.

 

[Phoneguy]

Feel the heater hoses going to the heater core. They should both be hot if you find that one is cold and one is hot you have a clogged core.

Or a bad control valve...

Bryan

 

[Buickforlife]

Very true. Both will do the same thing and cause his symptom.

 

[T What?]

I wish we all lived in the same Neighborhood. That would make life a lot easier. I will build the houses if you guys work on my car.

 

[Buickforlife]

Haha I wouldn't mind moving to Florida especially after the weather we have been having around here.

 

[Rich Gio]

If it was the core your floors would be wet and or your windows would be fogged up
First check the coolant level if low no heat
Second check the hcv with a mighty vac and make sure the line hooked to it is pulling a vacuum Third open the glove box door and look at the plastic L shaped lever that is hooked to the heat lever and see if it is broken and or functioning

Ok, I'm having the same issue. Not to Hijack but I moved the lever on the valve to full open and I get good heat. I checked the vacuum line to the valve and it has no vacuum with controls in car to full heat. Where does this line go... what should I check next?

 

[85begalttype]

ya sounds like a rusted stuck closed heater valve. vacuum lines from the intake manifold/throttle body run to a vacuum reservoir by the heater box, then go into the firewall by the ECM connecter(under heater box). From there they go to the heater controls on the dash.

 

[big dre]

Thanks Guy's for the Help..

 

[oddiesGN]

I would check the easiest first, start with the water level. Then I would check the vacuum line that goes to the factory air valve (it opens and closes water flow to heater core). Might of blew off the line.

Otes

 

[jlat]

I can't see the heat being any better than a properly functioning control valve. What would the reasoning be?

Bryan

hello; I got that from another site on vans I go to. Some are lacking heat and there's a few people there that's done it with good luck. It was told to me "it restricts water flow even when working correctly. There fore less heat" I still have to flush my core and maybe a new stat.
IBBY