Idles High

My car when you crank it up idles anywhere from 1000RPM's to 1750RPM's...it usually idles at about 700 or 800RPM's. What could be the cause of it idling so high. Also, when i get up on it black smoke comes out the tail-pipes. Does anybody know what it could be?


------------------
'92 RS w/ 305 TBI, Flowmaster 80 series, K&N Filter.....more mods to come.....gotta save up the cash first though

Definately check around for vaccum leaks around the intake manifold. Or any of the lines leading to and from it.

a spray bottle filled with water does the trick i'm told! Just spray small areas of the intake at a time at different sealing surfaces or orafices. goodluck!

Check the brake booster hose too.

Have you attached a scanner and tried reading the idle air counts? Should be around 20 - 30. If it is pegged at 0 then you may have a leak. That or a bad IAC and you could also try cleaning it then readjusting it.