So I found that something is unplugged omn the back of my carburetor when I plugged it up my RPMS shot way low and when I unplugged it they went back to normal.....just wanted to know what this little "nipple" is for?thanks!

 

If it is a hose, what is the other end attached to? Could be that the idle has been adjusted to compensate for the large vacuum leak there.

 

Honestly I dt even rember what went on that

 

Where's the hose from the carb to the vacuum advance on the distributor? Could this be where it goes?

 

I would guess mechanical vacuum advance. If your distributor doesn't have the vacuum line connected......that's probably where it should go.

 

I don't know if a '84 even has a vacuum advance can as a lot of gm's stuff was computer controlled carburetor and a computer controlled dizzy goes along with it. Here's a diagram that shows the vacuum line routing for a a '83. Also not trying to be a nit picker but dude, you might want to do something with that wiring before it causes you all kinds of problems down the road. I've fixed a bunch of electrical problems over the years and one of the most ridiculous ones I've seen was on a friends '79 Camaro. Someone had used wire nuts and electrical tape on the big main wire coming off the starter that feeds the whole electrical system! Anyways solder and heat shrink tubing or cold shrink tape(love that stuff) is your best friend when it comes to automotive wiring.

 

On my 84, that line goes to the HVAC system in the car. I'll take another look when I got out to lunch today, but I'm pretty sure that's what mine is for as it goes down behind the motor and into the firewall.

And yes, that's a massive vaccum leak! Plug it and re-adjust/tune your idle. Your carb has probably been tuned to run with that thing off/leaking and that's no good.

 

That "nipple" on the back of your carb is actually pretty important (assuming that is the stock Qjet). If it is not hooked up you will be throwing a SES code. The vacuum line that hooks up to is is a small diameter hard plastic line. It will be hanging out by the firewall on the passenger side of the car coming out of a wire bundle. if you are lucky, the soft rubber connector will still be on the end of it. If not you can grab an assorted package of them from AZ for a couple bucks.

 

That's where the MAP sensor is supposed to pug into, as razorN8 hinted at and you can see on rsmith's vacuum diagram.

But I don't see th eline anywhere in that monkey-abortion blob of hack job hanging out of that wire loom though, which is where it should be.

 

+1 wire nuts are the worst thing to connect wires under the hood. The second is those insulator piercing wire tap that just slip over one wire and then you insert the second wire and squeeze the tab into both wires. The exposed wire starts to corrode and causes a bad connection.

 

Yep.... I take a razor knife strip about an inch of insulation off, wrap the "feeder" wire around that then solder and wrap with cold shrink tape. I have been guilty of using them though, under the dash for stuff like acc on for radios but anything higher current or that could leave you stranded somewhere I always solder lol.

 

it could also be for your brake booster hose.

 

Not Sure What That Port Is On The Back Of Your Carb That You Have Capped Off,My Car Is Similar To Yours But My Carb Doesn't Have It,Also Looks Like Your Missing Your Carb Heat Insulator,And EGR Valve.

 

No, the brake booster is the big metal port you see on the back fof his carb. I'm 90% positive this one is for the HVAC or another sensor that's probably been disconnected. Either way, that port needs to be plugged and the carb re-tuned with it plugged to get the best efficiency out of it.

 

The small nipple on the base of the carb is for the vacuum sensor, which is located on the firewall on the driver side.

The large nipple on the air horn (which is plugged in the OP's pic) is a fresh air source for venting the EGR solenoid. It wasn't used on later 3rd gens (was on my '82, wasn't on my '86).

HVAC comes off of the intake manifold.