the idle speed on my 89 ranger (150,000miles) has been hanging up alot lately. Regular warm idle speed is like 550, but it hangs at like 900. I have read that on high mileage vehicles the butterfly shaft will get worn and physically hang up - is this true. I've heard that setting the idle up a little can cure this (which I would like to do, because I like a higher idle anyway) Why does it say idle speed not adjustable - because of emmisions? Need some ideas?
(I have cleaned the TB and it still hangs)
thanks
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1982 Mustang GT