The only SURE way I see of adjusting this correctly is with the right equipment, which only the dealer has, if not, then a lot of trial and error. Thinking about it I would say that it would be very dangerous if either the idle speed and mixture is not set propperly, you don't have a know variable and with two unknowns, you might try to fix a bad mixture with idle speed and vice versa, could bring about very bad results, but if you feel up to it, then let us know how it turns out.

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