My 1989 chevy k1500 4x4 5.7L v8 wont go above 40 mph
It sounds like you may have a fuel supply problem in getting the proper amount of fuel to the fuel injectors which may be caused by a bad fuel pump or potentially faulty fuel injectors. This can happen when the pump itself is not working properly or when the fuel pressure regulator is not maintaining the proper fuel pressure in the fuel system causing the engine to starve for fuel. This can also happen when there is insufficient connectivity to the fuel injectors which can cause an intermittent fuel spray pattern into the intake system resulting in a lean fuel condition or the motor otherwise starving for fuel. I would recommend having an expert from YourMechanic come to your location to diagnose your fuel system.
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