I have a 1995 gmc sierra 1500 sle with 5.7 liter tbi it's ideling rough spitting and sputtering and likes to idle down a lot and bogs out a lot what could be the problem replaced cap, rotor, plugs,
Have you checked the fuel pressure and all so check fuel filter, could be weak fuel pump.
im not sure if that year has the small filter thats located on the carb if it does you might want to replace that and the injectors could be plugging up if you unplug one of them you can tell when they are bad. they run about $60 and up i hope this helps you
That year has the fuel filter under the driver side door on inside of frame rail
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