I had an old carb'd Mazda engine do that once. it turned out to be a secondary ignition failure. It would idle smooth as silk, but try and go up a hill, or some other load, and it would stutter like Jerry Reed on crack.
Turned out I had replaced the plug wires with new ones, and one of the new ones was bad.
Check your cap, rotor, and wires.


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TripleJack

85 GenI SWB 2.5/5-Speed on 33s

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