46 is for coil 1 , 47 is for coil 2
Not necessarily. Another simple test to perform is to disconnect the electrical connector to the idle air control valve. If there is no change in idle, the IAC valve is bad.
I would also check for vacuum leak. Usually, vacuum leak will render the engine with erratic idle, similar to your description.
Sunday, March 1st, 2009 AT 12:19 AM