wont idle

[GreyGoose006]

my 84 caprice refuses to idle.

if i have it in neutral/park, it barely keeps going without my foot on the gas.
if it is in drive/3/2/1, it wont go at all.

i found a vacuum leak in the main vacuum line off the back of the carb, and fixed it with electrical tape and it seemed to get worse believe it or not.

i didnt do anything to the car to cause this sudden nonsense.
i was driving home and in the middle of the downtown tunnel, it died (i was idling). i restarted it and made my way home and looked for a fix.

im really about at my wits end here.
help

[PeteA216]

Try fixing that vacuum leak properly. You'll never get a good seal on a vacuum hose with duct tape.

[silicon212]

Check all of your vacuum connections and hoses. Sounds like a vacuum leak. Also, make sure the carb is tightly bolted to the intake.

Have a buddy start the engine and keep it running, while you listen for hissing sounds (obvious leaks) and spray WD40 around and listen for changes in engine RPM (less obvious leaks).

[PeteA216]

Instead of WD-40, I like to use carb cleaner because it leaves a lot less residue and still gives and obvious location of a vacuum leak. If it turns out not to be a vacuum leak, the EGR valve may be stuck open, but since you said it happened while sitting there in idle, then the odds are leaning towards a vacuum leak. Spray the carb cleaner (or WD-40) on the carb base, at all vacuum hose connections including the brake booster line. Spray at the base of the EGR valve in case the gasket went, etc.