94 lesabre 3.8 liter has high idle codes read quad driver failure, replaced idle air control valve but did not fix problem . vehicle will run high idle and when you turn engine off and try to restart you may have to wait 10 to 20 minutes before engine restarts . can unplug mas air flow sensor and vehicle will drop down to low idle but surges. any help would be greatly appreciated

 

just wanted to let everybody know i replaced the ecm and that solved the problem with the vehicle it also solved the no speedometer problem that the vehicle had .