Maybe someone can help me out, I am not able to get any hot air from my heater. The car runs at normal Temp, I replaced the vaccum switch under the hood, and anti-freeze level is normal. Heater switch on the dash seems to be working right. If anyone has any ideas I would appreciate the help. Its gonna get cold soon!!

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i'd guess your ducting, or doors, whatever it's called aren't getting opened or closed. look for a vacumn leak in the heater controls and look for something being stuck or broke in the vent system. good luck i fought a similar problem for weeks looking for a vacumn leak, after i knew i had a leak. just couldn't find it.

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-=ICON MOTORSPORTS=-

 

its not blowing hard??? or the air isnt very hot? well if its not very hot your thermostat could be too low and your fan switch might be too low. your engine needs to be warm for the heater to work. or maybe your heater core is going to die soon. hopefully not

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Rick
90 Camaro RS 305 TBI
350 on the way!!

 

I'm sorry Black Beauty, but I don't know that the temperature of the engine holds true for heater temperature. My Iroc, has a 160 degree thermostat, and plus my fan is rigged (getting ready to unplug it though) at this time, and my heater gets very hot! Extremely hot for that matter! I have to turn it off and crack the window a bit. I think DROPZTOP89's problem is in his heater core.

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"Clear your mind, relax, and float downstream."

 

What year, make and model is your car along with engine size?

Another thing to check...

Are you referring to the vacumn switch as the diverter valve? If not then check out the diverter valve on the passenger side engine compartment...behind the AC. It should have a vacumn line running from it to the controls in your car. When you flip the heater on the vacumn opens the diverter valve allowing the coolant to then flow through the heater core and thus giving you heat. The diverter valve may be going bad or you may have a break in that vacumn line...good luck trying to trace it b/c it runs into the wiring harness (at least it does on my car). If it was your heater core I would imagine you would have antifreeze in your passenger's side florboard.

Have you made sure the switch in the dash is working properly...i.e. activating the vacumn controls? They may be old/dirty and a shot of electric parts cleaner may help but I'm no expert on the switches for the AC/Heater controls. Pull your AC/heater controls out and look on the back to see if everything is plugged in.

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1988 TA 300+hp 350 w/ TBI and Holley TB unit, Holley projection intake,
WC T-5, 3.42 gears w/ Auburn posi. MSD 6A, edelbrock TES headers, dynomax 3" cat and cat-back system, ACCEL coil, polyurethane bushings all around, aluminum driveshaft, Mr. Gasket open air cleaner.

1993 S-10 w/ 4.3L V6 TBI, slightly bigger cam, Mild polish job and 3 angle valve job on heads, Edlebrock TES headers, Dynomax cat back, MSD 6A, ADS chip

2000 Kawasaki KX 125

 

how long have you owned the car? and have you ever used the heat before? maybe the heater core went bad and the previous owned just disconnected or looped togehter the hoses that run to it. make sure you have 2 heater hoses running into the firewall on the pass side. one will be 5/8 and the other 3/4...if you dont see the hoses, (they should be a little to the left of the distributor) or if theres just 2 short pieces of tubing (that look like they should have hoses on them) sticking out of the firewall, thats your problem

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350, Comp 262, Edelbrock Performer intake 600 cfm carb and exhaust, headers

 

Thanks for the feedback, I should have mentioned that the car is an 89 Formula, 305 TPI, that is totally stock. The car was purchased by my Mom and dad brand new, and was driven by my Mom until this past May. It is a Florida car, but they did use the heat in the winter time on occasion. They did have a problem with the fan switches and they were replaced not too long ago. Gonna check the heater controls today.

 

ede, badbird88... it's "vacuum" not "vacumn". Just thought I'd give you a heads up...

 

I too will second Black Beauty's comment about a "weak" thermostat. When a thermostat gets old, it will sometimes not open fully and/or close fully. Thus you get the worst of both worlds, won't let the car heat up fully in winter while not cooling fully in the summer. This will become especially noticeable if you just moved from Florida to New Jersey.

I have found that around 5 years is about the maximum life I have ever gotten out of a thermostat (opening and closing properly). Usually, after 5 years, they start to get "weak", though not fully failing.

 

Can anyone answer this?? When my car is sitting there idling, it blows cold air through the vents. When I am moving or keep the car above 1500 rpm the car blows hot air through the vents, can anyone tell me any info?? Cause the weather is getting colder.


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Godti
'89 Trans Am (Red)
305 TBI 5spd