Mechanically, the throttle is just a glorified butterfly valve. The throttle position sensor could cause symptoms similar to that, but wouldn't cause the cycling you describe (assuming your foot remained in the same position). Plus, problems with sensors like that don't usually just go away upon a restart.

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A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.