My Dad gave me his 1984 honda civic 1500 s. Great shape! EXCEPT! 3 years ago the timing belt broke and it di dnot run right after that. The mechanic said he needed another carb. Dad said bull **** and parked it in the hanger. 3 years later I have it and it runs fine except it will not idle below 1200 rpm and shots down most every time you take your foot off the gas.
can someone please give me ideas.
Is the belt a tooth off?
Vaccum problem?
timing off?

 

First, get the 84-87 Civic manual here:

http://hondatech.info/downloads/Auto/Manuals/Civic/

Check the TW sensor, the PCV valve, the Fast Idle Valve, and adjust the idle speed.

Is the PGM-FI light ON? Is the ECU lamp blinking a code?

 

it was the engine shut off selenoid.

 

Glad you got it fixed, make sure you keep fresh fluids in that classic. They even have new oil made for high mileage engines.