My first guess would be ISC (Idle Speed Control) Servo. Not sure where it is on the 3.5 but on the 3.0 SOHC it's right next to the air intake (4:00 position) on the engine throttle body. It simply needs to be removed and cleaned with a lint free rag.

Also remove the intake hose (may be easier to access the ISC when you do this) and clean (using a rag w/out solvents & don't use carb cleaner) the inside of the throttle body as far as you can reach.

Ray <img src="/forums/images/graemlins/kewl.gif" alt="" />

Off Roader
98 Montero with the Winter Package
89 Montero minty clean and reserved for overlanding trips or Cars and Coffee events
96SR (3.15:1 xcase, 35's) gone to the rust gods
96SR Build Up Thread
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