[Ironbug]

My 03 Focus is running good down the road but its having trouble idling after it runs for a while. When i first start the car it runs smooth at idle. Then as it gets warmed up the idle turn really rough like its missing then just dies.

i have chased the problem a little but thought i would ask to see if anyone else has had the issue.

i replaced the spark plugs, upgraded the chassis ground, checked the air filter and cleaned the throttle body.

any thought on what i am missing?

thanks for any help.

 

[djmontara]

clean your IACV

 

[Ironbug]

I found the problem. It wasn't the IACV but looking in that area let me hear the vacuum leak. It was the intake house that runs from the right side of the valve cover to the intake manifold just below the throttle body. The hose has a 90 degree turn right were it connects to the intake. It broke off at the turn.