Brunton

Hi,
Sorry to bother anyone with this question. I actually think I saw a thread on it but can't find it now. I was running my '82 today and it suddenly went wacko. The car was idling down to almost dying, then coming back up to 1000 RPMs. When I pulled the lid off the air cleaner I realized I was getting a lot of vac on the hose that goes down next to the idle compensator. I'm talking about the on on the driver's side of the air cleaner, that isn't the idle compensator line. It appears to hook in at the base of the carb near the firewall. I found that if I plug the line it would idle good. I currently have the hose plugged with a bolt and the hole in the air cleaner plugged as well.

What I really want to know is why is this affecting my idle this way? Is there any reason I can't set this like this permanently?

Thanks

twinkletoes

iTrader: (17)

Yep, thats the shutter valve hose you plugged. If you take the lid off and the bolt out to unplug it and you hear a loud honking noise, the shutter valve is bad. Just plug it and you'll be fine. It wont hurt anyting plugging it. Its just a peice of crap.

Rx-7Doctor

iTrader: (13)

Actually the shutter valve is part of the emissions. It's purpose is to shut off fuel to the rear housing during deacceleration. This also can help with fuel economy.

Brunton

Ok, thanks. So basically, if I don't care too much at the moment about my fuel economy I can leave it plugged and not worry bout it.

inuissus_cendi

Yes. I removed mine and am not looking back.
Where in Minnesota?

PercentSevenC

That thing sure caused me endless problems.

vipernicus42

iTrader: (4)

Removed mine, no problems.

I was told to leave the butterfly in place and JBWeld it straight up and down, but to just take the shutter valve itself out and seal up the vacuum holes.

I had a friend also take the butterfly out, but once he did he couldn't get his idle below 1,100rpm no matter what we did.

I originally left mine in, but then got my manifold ported so it's no longer an issue.

Either way, the shutter valve is about as useful as an appendix. Toss it in the bin with the hot start assist, cold start assist, useless "block heater", airbox snorkel flap, exhaust heatshield and pipe to snorkel and (if you don't have emissions testing) the rat's nest, acv, and air pump.

Jon

inuissus_cendi

well I think I just found the cause for my idle to be at about 1,100rpm...
haha I tried forever to figure it out but just gave up since its not THAT high. I removed the butterfly at the same time as I installed a new carb and removed the rats nest... never even occurred to me that it could have something to do with removing the shutter valve butterfly.

bliffle

My 83 started honking about 4 years ago, so I popped a carved cork into the appropriate hole in the floor of the airbox, determined by applying a thumb over each hole 'til I found the right one. Then, months later, while treasure-hunting at the PnP, I found a perfect rubber cork with a retainer cap in a junk cars airbox. Lucky me.

Biggie Calves

Wait a minute Wait a minute. Are you saying just removing the actual butterfly's plate from the shaft will cause high idle, or removing the entire assembly does? (Aluminum housing with the diaphram etc.) Not that I see how doing one over the other would make a difference, but hey I'm not going to assume anything.