Good day,

I have a '90 Silverado with a 5.7 throttle body injected motor. It's standard original equipment under the hood and I've had this truck for 10 years. For the past several months, the motor has not run well. It will idle fine, but then when I so much as touch the gas pedal, the motor bogs and often dies. I've discovered that the spark plugs are fouling out rapidly. I rebuilt the fuel system - tank through throttle body - two years ago and was off and running like new up until this problem a few months ago. The injectors appear to be functioning fine and the spark plugs have low miles on them. After running the motor, I remove the plugs and they are all covered in black soot. That seems to be a fuel fouling issue. I clean the plugs, put them back in and can drive just fine for about 2 miles then the motor will not run well and frequently dies at the touch of the throttle. I pull the plugs again and they're all black. There are no codes, so I get no help there. One strange aspect of this is that the motor frequently picks way up in RPMs by itself and then does the bogging/dieing thing. Do you have any potential solutions? Any similar experience?

Eye thank yew for your time.