The engine would start but not continue running. Would do this several times on 1993 GMC Suburban 2500

Would have to put it in park and turn key totally off. Had the fuel filter replaced, tune up w/ new plugs,wires ect. Started better, but still has a miss and terrible fuel mileage. Have had several 454's so know about low mileage, but this is bad. It had a fuel pump indicator code at first, replaced relay on wheel well, code went away. This time no codes for bad idle.

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