no heat! 
no heat!
TECH Resident
Joined: Apr 2010
Posts: 787
Likes: 0
From: T E X A S
vacuum is the one on the engine harness, the only one that is actually a part of the loom on the passenger side... try popping the line off and see if you can run some water through it with a hose to make sure it isn't clogged.
When I got my '94, the heater core was clogged. Pull the hoses off the engine end and using a water hose, send water in one end while the other end is pointed at the ground. When it clears, you'll be surprised how much gunk comes out. Do the same in both directions.
While you're digging around in there, check the vacuum check valve. They get brittle and crack.
http://shbox.com/1/vac_check_valve.jpg
Reassemble, top off and bleed. Enjoy the heat.
While you're digging around in there, check the vacuum check valve. They get brittle and crack.
http://shbox.com/1/vac_check_valve.jpg
Reassemble, top off and bleed. Enjoy the heat.
TECH Veteran
Joined: Dec 2008
Posts: 4,145
Likes: 61
From: Little Rock, AR
Vacuum has nothing to do with temperature control (only mode control). Temperature is controlled by a cable from the **** to the blend door.
If your heater hoses are cold, then there is probably a restriction. Flush it out.
If your heater hoses are cold, then there is probably a restriction. Flush it out.
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TECH Veteran
Joined: Dec 2008
Posts: 4,145
Likes: 61
From: Little Rock, AR
Just pointing out what controls what because the OP indicated he thought vacuum might be a suspect for heat.I've had to replace my vacuum check valve. The new ones look a bit different.
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TECH Fanatic
Joined: Oct 2006
Posts: 1,106
Likes: 0
From: POULSBO WA.
Would a fualty thermostat have anything to do with it in these cars? I have the lower 165 temp stat in mine and it takes forever to get warm. Almost want to go back to stock in the winter, but i am smelling anti freeze inside the car...so i am going to have to change it. Maybe i have a clogged one too.
TECH Veteran
Joined: Dec 2008
Posts: 4,145
Likes: 61
From: Little Rock, AR
A faulty themostat could restrict flow. If you smell coolant inside, the heater core probably has a leak. Hoses and/or core could have some clogs. You could have all three things going on.
Would a fualty thermostat have anything to do with it in these cars? I have the lower 165 temp stat in mine and it takes forever to get warm. Almost want to go back to stock in the winter, but i am smelling anti freeze inside the car...so i am going to have to change it. Maybe i have a clogged one too.
I'm assuming your car is tuned for the 165stat? If not it'll just take longer to reach operating temps, you should still feel heat eventually.
TECH Regular
Joined: Oct 2011
Posts: 407
Likes: 2
From: Keller Tx
I know this is crazy but my heat works fine on warmer days above 60 degrees but when I need it no heat is there. The blend door is cable operated? The core is good and has been flushed. Above 60 degrees I can turn the cold/warm blend door back and forth and works good.
It pisses me off. How can this be so damn difficult!
It pisses me off. How can this be so damn difficult!
