Search is your friend- the answers are on the board. Start with Idle control Valve (ICV) but there is much else you should check as being clean and fully operational... but the ICV and vacuum leaks in the intake side of the motor are the most likey culprits. You may have a leak just started in an old hose or connection. Checking the ICV's operation is within spec is the first thing to do; see the Bently manual for the procedure and test ranges it needs to be within.Originally Posted by RAZR