Heater issue

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226gpd
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Joined: Fri Dec 14, 2007 9:14 pm
Location: Greenbrier,TN

Heater issue

Post by 226gpd »

Heater switches from cold to warm but doesn't get really hot. Just replaced the thermostat so I know the motor is warming up. Vacuum issue??
Thanks for any help
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JohnLynch
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Re: Heater issue

Post by JohnLynch »

226gpd wrote:Heater switches from cold to warm but doesn't get really hot. Just replaced the thermostat so I know the motor is warming up. Vacuum issue??
Thanks for any help
You check your coolant? I know this just happened to my truck and the water pump was bad and it had no coolant.....
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226gpd
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Location: Greenbrier,TN

Post by 226gpd »

Thanks for the reply..Coolant is good. I'm thinking the door that switches from hot to cold is sticking...but I'm not sure..I've owned many fox body Mustangs but never ran into this problem before.
2002 Corvette Z06
2000 Saleen 00-0134 (SOLD)
1993 LX 5.0 Coupe Reef Blue (SOLD)
1997 Saleen #59(SOLD)
93 Cobra #418 (SOLD)
2000 Saleen SC281 Convert. (SOLD)
93 Cobra #3398 Black/Gray(SOLD)
93 Cobra #4019 Red/Gray(SOLD)
2003 Cobra Convert. (SOLD)
1996 Saleen (SOLD)
1989 Saleen Convert. #80(SOLD)
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WillyB93
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Post by WillyB93 »

The cable end tends to break the flapper for the heat to cold, may have to follow the cable to see what is happening.
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Mike S.
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Post by Mike S. »

Probably a partially plugged hater core. Try flushing it out in both directions with a garden hose, a lot of ugly brown muck should wash out. If still luke warm, flush with pool acid cut 1:1 with water, let sit for 5 minutes, flush again. Repeat if necessary. That should do it.

-MJS
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SPEEDFREEK
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Post by SPEEDFREEK »

Is the temp coming up like normal? I've seen new thermostats that are bad and stick open. I just did one in another car that did that. It was stuck open and the heat would just get warm it wouldn't get hot.
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KeystoneJohnny
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Post by KeystoneJohnny »

Mike S. wrote:Probably a partially plugged hater core. Try flushing it out in both directions with a garden hose, a lot of ugly brown muck should wash out. If still luke warm, flush with pool acid cut 1:1 with water, let sit for 5 minutes, flush again. Repeat if necessary. That should do it.

-MJS
I would say this or the flap due to the cable issue as mentioned by the mod
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226gpd
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Joined: Fri Dec 14, 2007 9:14 pm
Location: Greenbrier,TN

Re: Heater issue

Post by 226gpd »

Thanks for all the input..Apparently the heater core was just dirty. I flushed it out today and it is warmer.
2002 Corvette Z06
2000 Saleen 00-0134 (SOLD)
1993 LX 5.0 Coupe Reef Blue (SOLD)
1997 Saleen #59(SOLD)
93 Cobra #418 (SOLD)
2000 Saleen SC281 Convert. (SOLD)
93 Cobra #3398 Black/Gray(SOLD)
93 Cobra #4019 Red/Gray(SOLD)
2003 Cobra Convert. (SOLD)
1996 Saleen (SOLD)
1989 Saleen Convert. #80(SOLD)
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