This.Exhaust.Valve.... What is it?

[y5e06]

Frankly I'm not used to the 80's smog motors. More of a late model guy.
1987 Monte SS. stock.
I drug this car out of storage after a decade. Looking it over I see this valve is disconnected and the arm is basically rusted.
Is this a butterfly valve right in the middle of the exhaust stream? Which way do I need to wire this valve open? I'm not going to tear the exhaust apart now nor am I going to fix this to make it functional for the EPA...

also, first time in the sun in over 10 years... shamefull, i know.

 

[pontiacgp]

that is the EFE, early fuel evaporation

 

[y5e06]

do I need to wire it open? or just leave it flapping in the wind?
what are the specific function modes?

 

[pontiacgp]

it was vacuum operated from a thermal vacuum valve. When the coolant was cold it would close the flap and when the coolant heated up the thermal vacuum valve would close the vacuum to the EFE and the flap would open assisted by a spring. If you are not going to remove it I would make sure it stayed in the open position so it stays quiet.

 

[y5e06]

thats for the follow up.
which is the open position? the vacuum actuator is pretty dead. and there is no apparent resistance either way w/ the valve.
if I do no thing, will it restrict the exhaust flow? from that location of the pic, it *appears* to be in the exhaust stream but maybe not.

 

[406 Monte]

Welcome from Minnesota! You found an awesome forum with great people and info!
That's a sweet look'n Monte!!!

 

[pontiacgp]

thats for the follow up.
which is the open position? the vacuum actuator is pretty dead. and there is no apparent resistance either way w/ the valve.
if I do no thing, will it restrict the exhaust flow? from that location of the pic, it *appears* to be in the exhaust stream but maybe not.

I'm not sure but the vacuum actuator will pull the rod in so when the rod is fully extended that would be the open position.

 

[y5e06]

Thanks again.

thats for the follow up.

(this meant to say Thanks, not thats)

 

[y5e06]

https://www.thirdgen.org/forums/exhaust/714798-l69-pass-side-efe.html#post5876794
found this post on 3rd gen. pretty good shots of the EFE.

 

[Bonnewagon]

If you intend to use the car in Winter, then you should repair the EFE valve. They are available and it serves an important purpose. If not, then either wire it open or remove it and use the casting without the valve. What it does is- in the closed position it forces all the exhaust gas from that side- back up through the exhaust crossover in the intake manifold- then out the passenger side exhaust manifold. If it stays shut you can boil the fuel in the carburetor. Once the motor heats up it opens and both sides flow normally.