i was driving home yesterday and my 87 with a 5.7l started idling at 2k. i parked it and found a vaccum leak and fixed it thinking it was the problem. it only lowered the idle down to 1500 rpm. check engine light is not on so i am assuming there is no trouble codes. so i am out of ideas and any help is appreciated.

thank you

 

has anything gotten wet. Mine did that for about a week after I washed my engine.

 

Replace the vacuum lines.

Could be the TPS (throttle position sensor). Top connector,pass. side of T/B.

Could be a dirty IAC valve (Idle Air Control). Big circle looking thing below the TPS on the pass. side of the T/B.