Hey guys i recently bought an el fairmont on dual fuel and since i bought it ive started having some problems with it idling. It idles at about 2 grand and i cant get it to idle any lower, tried turnin the idle screw, And ive changed the sensors etc on the throttle body abd nothing changes. If i unplug the idle control solenoid it idles normal again but ive swapped the solenoid with one that i know works fine and it made no difference. Anyone got any ideas what it could be? Could it be a problem in the ecu?

Clean the new ISC out (the known working one) then set your base idle correctly by unplugging the isc, have the engine running, put a 0.75mm feeler guage between the grub screw on the TB and the throttle, wind idle down to 600~650, (should JUST barely idle) remove the feeler guage and plug the isc back in, done. Give it a few days to relearn, wouldn't hurt to disconnect the battery and reset the ECU too.

Cheers! Yea reset ecu yesterday to see if that did anything. Il give the isc a clean etc tomoz