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The idle air control valve can be cleaned with relatively good success with carburetor and choke cleaner before you buy a new one. I would recommend trying it. The other thing to check is to make sure the EGR valve is not sticking on to tap on the EGR or apply vacuum make sure the plunger is going fully closed otherwise it will make it difficult to idle. Let me know what you find.
The only way to accurately clean the idle air control motor is to remove it from the bottom of the throttle body and spray the duty cycle valve or flapper valve that rotates back and forth. Carbon gets built up on it and it is difficult to clean by spraying carburetor cleaner down in the hole of the throttle body. The EGR valve is located on the backside of the intake manifold just after the throttle body assembly. There is a metal pipe that goes from the bottom of the valve down to the exhaust port on the cylinder head.
Let me know how it goes.
Click the link below and save for more information. This engine does use and egr valve.