Dodge Repair: fast idle on 98 dodge ram 1500

Question
Been having problem with check engine light, used scan tool to retreive code PO308 misfire on cylinder 8, erased code.  Had ignition on but not started, when i removed the tool i forgot to shut off the key.  Next morning went to start pickup and found it was in the on position and would not start.  Boosted with another vehicle and when it started it was on a fast idle and remains that way.  What could have happened?  Help

Answer
Hi Barbara,
Did you try to use the scan tool to retrieve any new fault code? That would be the first thing to try.
Other than that there is an automatic idle control mounted in the throttle body and it may just be gummed up. You could try cleaning the throat/butterfly plate/side passage airway (which feeds air to the automatic idle control) with some mild solvent and then see if the a.i.c. has resumed its normal function. Let me know what you learn/find. Let me know which size engine you have if you send a follow-up question.
Roland