High idle is all vacuum leaks. You have to replace ALL lines on the motor to fix it. I recently did this, you even have to replace the injector bushings (the plastic piece the injectors mount into the engine with) as they have o-rings that can leak air.

When I did it I took the whole thing apart right down to the throttle plate. Replaced the main air boot on the bottom of the Air meter assembly too, old one was hard as a rock.


Before all the work mine idled around 1200 in park, and was loading it up in drive/wasting gas. Now it idles around 600 in park, 550 in drive and it much more calm. MPG went from an average of 14 city 21 hwy to 16-17 city and 23 hwy.

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