5.7 fuel problem
I have a 5.7 litter motor in a 1998 z71 chevy p/u. My gas millage is terrible and it misses as I'm going down the road. My millage is 320,145 miles well kept with real no problems till now.
Is the check engine light on? Have you had the compression checked? Possible intake manifold gasket failure. Possible fuel spyder problem. You said it was well maintained so I assume that the cap, rotor, plugs and wires have been replaced.
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