heater... arrghh...
Thread Starter
Le Mans Master
Joined: Jul 2003
Posts: 7,501
Likes: 1
From: Maine
heater... arrghh...
ok... i replaced all the vacuum lines (thanks to all the info here!) and got the defrosters and vents all working.... the ac isnt hooked up but thats ok..... but the heater is blowing warm air at best.... am i missing something? i looked for a shut off and didnt see one...it got plenty hot in the car and on the passenger side this summer ....
Thread Starter
Le Mans Master
Joined: Jul 2003
Posts: 7,501
Likes: 1
From: Maine
theres a switch on top of the heater box where the cable attatches... it looks like it has a little plunger on it and as you slide the lever from hot to cold it catches that plunger about half way and pushes it in....... seems like its working correctly.. could that plunger be the issue? should it be coming out more?... and could it be as simple as no thermostat?
Pro
Joined: Oct 2006
Posts: 734
Likes: 0
From: Bryan Texas
I imagine the cable just needs adjusting, not sure what the plunger is. Take the cable off and check the door travel, all the way one way is closed and you should get no to very little heat, the other way is full heat... just make sure the cable closes the door tight when the setting is set to cold.
Pro
Joined: Oct 2006
Posts: 734
Likes: 0
From: Bryan Texas
I'm not sure.. on my c4 you can take a module out of the casing in the engine compartment and see the door working, maybe the same on a c3? You can tell a lot just by moving the door arm with your hand.. if it "feels" right, it probably is. Just check that the cable is moving it all the way shut.
Thread Starter
Le Mans Master
Joined: Jul 2003
Posts: 7,501
Likes: 1
From: Maine
i was letting the car warm up and after about 10 minutes is was blowing hot! i went for a ride and it cooled right down. i got a 180 thermostat... im gonna try that tomorrow... i dont see a way to check the door but there is a vacuum plunger on the top of the heater box.. if the thermostat dont cure the problem... thats next on the list......
Thread Starter
Le Mans Master
Joined: Jul 2003
Posts: 7,501
Likes: 1
From: Maine
ok.. theres a little vacuum controled plunger on top of the heater box.... i have searched for it and cant find one.. i think its leaking and causing the no heat issue.... anyone.. whats it called? i searched the site and the major vette parts sites and cant find one....
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Drifting
Joined: Apr 2008
Posts: 1,305
Likes: 2
From: Lewisburg WV
thegazman
That little plunger is the valve that allows vacuum to open you heat control valve inside the engine compartment. When you push the temperature lever to the coldest position on your heater/Air conditioner control on the dash the cable closes the heater door and tab on top pushes in on the spring loaded plunger shutting off the hot water from the engine.
