1990 Roadster No Heat!!

[roberer]

I have no heat in my car. I've replaced the AC Control panel, checked all mechanical points (wires/Vacuum) flushed the Heater core. I get full cold no matter what I do. The venting options change from Automatic, to dash, to feet vents but the temperature never varies from full cold.

Anyone had or have a similar malfunction??

 

[taegdh]

Heater malfunction

On one of my varied vehicles I had the cable break between the control panel and the valve which allows the heatant (coolant) into the heater core. It was a 72 Nova, and I found it by chasing the cable to the controller valve and found it wasn't moving when the heat quantity selector was moved. Took the better part of an afternoon to replace.

Check it out for yourself...

Have a good New Year.....

 

[Brianjt1987]

I had a 94 Camaro vert that I bought new in 94. Every couple of years there was a small metal by-pass hose that would always develoup a hole in the exact same spot. I later found out that the engine was full of sand (from the casting of the block) when I had the same thing happen to a freeze plug. While it was being repaired the mechanic asked how all this sand got into the engine, I had it flused and the problem went away, or so I thought. As several years passed the heater lost more & more heat and though I never took it apart (I was living in S. California) I am pretty sure that the heater core had filled up with sand.

I pulled the heater hoses off and tried to flush it out, with no luck, so based on the fact that I maybe used it 3 times a year I let it go. I think that in the heater core, the coolant comes in on one side & exits out the other. The collant can travel through any of the cooling veins, so you could have 80-90% of the veins blocked & you would still have coolant flow, But not to much heat. I think the only way to correct it is to have the heater core pulled and taken to a radiator shop where thay can pull the side tanks and clean it right.

May not be your problem, but it sounds alot like my Camaro heater. Good Luck.....

Brian

 

[Magmotor]

You might want to check out #15 & #24. More than likely it's 24, the AC/Heater control valve. Good luck with it.....

 

[jmccloud]

No Heat

Do you have 'manual' or 'electronic' temperature control? I think it's C60 or C68 option?
I have the 'manual' control on my '95. Check my first threads by searching via the tab above. It was really weird, the A/C compressor ran all the time. Turned out it was a shorted transistor in the control head. If you have a similar system (different year!) and if you have automatic temp control, you could have a similar blown transistor, or perhaps several. Mine was easy to diagnose because the faulty transistor looked like a peeled banana.
On the other hand, if you have 'manual' temperature control, it could be that your control cable is 'bad'.
Mine was broken at the control head end (in the dash). The cable sheath attaches to the passenger side of the control head and must stay fixed as the control wire slides inside to open and close the temperature door. On my '95 the bracket that holds the sheath was broken off so the sheath moved with the wire as the slider was moved. So at the heater door end, nothing happened.
Some creative 'engineering' (a wire tie) fixed the sheath at the control head and now heat flows.
If you can't picture the 'sheath' and 'wire', visuallize a lawn mower throttle control.
Hope this helps.

 

[Vettefan87]

This happened to me. The car would sometimes spit out heat, and sometimes it would spit out cold air. I checked the antifreeze, and it was low, I might check that if I were you, before you start to tear into things.

 

[Edmond]

This happened to my Toyota Camry. There was no heat at all, the air was cold. It happened to be the heater control valve.

On my Toyota, it was connected to the firewall by a few hoses. I'm not saying it's the same with the Vette' but definitely take a look at it.

Get it done soon because not having heat really sucks. I use my Toyota for work and sitting in that car for 6 hours without heat in 5 degree weather isn't fun. :cry