Engine Performance problem
1990 Chevy S-10 4 cyl Two Wheel Drive Manual 190000 miles
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At a certain low throttle position it will spudder and sometimes die. Give it more throttle and it will clear up. When engine idles back down it will do the same. At freeway speeds approaching 70 mph it begins to spudder and lose power now mattter how much throttle you give, it will slow down. Driving 55 to 60 mph no problems? I believe it to be fuel related. It had a recent complete tune up.

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