wont idle

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. :banghead:
help

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

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).

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.