carburetor stock holley 4180 major problems

[84-4eyed]

Ok new here and new to forums as well but I decided to try it out cuz my "new " 84 mustang gt vert is giving me some what a hard time okay so I just got this car not really knowing about the carb so first day I got it ran OKAY not great do to the fact at idle it would want to drop idle and shut off at times okay next day car turns on but starts but idles down and shuts off if I give it gas it will stay on okay no biggie maybe alternator or battery so I go charge the battery put it back boom she stays on But did want to idle down at times so I mess with the idle screw a little and she was running like a champ didn't cut off coo next day it happens again but I notices under the fuel line connected to the carb is a vacuum hose that is cut hmm okay it still ran like that so i noticed there was a bolt laying on the intake manifold laying right under so after doing who knows that to the idle screw it stays on but today i washed the engine covered the carb and distributor tried turning on and she didn't want to stay on she started to bogging so i rev it up to 4k rpm for a minute or so and she stays on so i took it on a test ride just a block away i was going home and out of no where i hear a kinda loud noise and out of no where i don't have acceleration BUT the rpms shoot true the roof I'm talking about i never seen rpms increase that fast yet not going very fast so i quickly turn off the car and hear a back fire so i roll it to park and try turning it on and it starts and idles at 2k rpm weird wasn't doing that this morning so i let the car idle like that and put my finger on the broken vacuum hose (if u haven't notice i don't have a clue where its meant to be) and it idles down just to around 1.8k not much of a different the throttle screw is basically loose yet it still idles high please help i tired looking at vacuum diagrams but cant find one about the vacuum hose under the fuel line and a hole in the intake manifold close to that vacuum line behind the alternator if any one can help it would be very appreciated ... i will try to add photos

[Walking-Tall]

Yes... photos... please...

[84-4eyed]

here they go first one is the broken vacuum hose i was talking about second one i noticed my fast idle cam is getting stuck probably the reason my rpms went high so when i have it all the way up the throttle doesn't go down all the way and idles around 1.6k to 2k but doesn't drop after engine is warm like it supposed to third photo i pull it down and the throttle goes back to normal place and idles right around 1k but i noticed when i give it throttle the chock doesn't move.. and thanks for the reply didn't think i was going to be able to get one ow yeah the broken vacuum hose looks like its on a spacer under the carb ill take another picture when i get home

[Walking-Tall]

Okay. Any broken/open vacuum lines need fixed/closed.

Is the choke cap on the side adjustable? Is there voltage at it's electric choke wire with the key in Start/Run? Some lubrication of the choke linkage and the plastic arm's pivot never hurts, especially in case it's sticking "on". The fast idle RPM is adjustable with a small screw (engine off, wide open throttle... then you'll see the screw's head pointing downward, below/behind the choke housing... takes something like a 1/4" wrench to turn) that resides at the other end of the large plastic arm, at it's steps for fast idle.

[xctasy]

Choke pulldown requires a 17-20"Hg hand gauge to set.


Carb has four corner idle. Don't adjust it. If you do, you have to use JACook's (post below) propane torch method, and be patient.

1. Throttle drop matters can be purley mechanical....check this first.

http://vb.foureyedpride.com/showthre...0C-going-crazy

85stanggt's a 1985 GT, very different, but the other check is

actual vaccum at distributer, and the 17"-20"HG with hand vac pump choke pulldown adjustment.


http://vb.foureyedpride.com/showthre...rade-Questions
The 8 pages of http://vb.foureyedpride.com/showthre...er-start/page1


A very good reference has been Saturn V 's posts, but none of the picture links remain.


Start at post #35

http://vb.foureyedpride.com/showthre...uestions/page2