97 CHEVY K3500 DIESEL 6.5 TURBO NO CHECK ENGINE LIGHT ON SURGES BAD OFF IDLE REVS UP AND DOWN BY ITSELF HAVE GOOD FUEL PRESSURE AT FILTER HAS SOME BLACK SMOKE AT TAIL PIPE WHEN REV UP HAS CODE IN HISTORY P1216 P1218 RELATE TO FUEL SOLENOID DRIVER IAM STILL NOT SURE THAT DRIVER CAN CAUSE THE PROBLEM IAM HAVING I JUST DROVE TRUCK IT TOOK OFF ON ME WHEN DRIVING HAD TO SHUT OFF ENGINE RPM JUMP UP AND TURN OFF LET SET FOR A MIN THEN RESTART IDLE OK TOOK BAD TO SHOP NOT SURE FUEL SOLENOID HAS ANYTHING TO DO W THAT ? THANKS FOR HELP
The injection pump delivers fuel to individual cylinders by opening and closing a solenoid control fuel valve. The PCM monitors the amount of time it takes for the fuel solenoid valve to physically close after commanded to close. Closure time out of range is seen as a fault. This response time is measured in milliseconds & when incorrect a P1216 is set.
The PCM uses a calibrated resistor mounted internally in the injection pump to determine fuel rates. The resistor value is stored in the PCM memory. If the PCM memory has been disturbed or the PCM has been replaced, the PCM will relearn the resistor value on the next ignition cycle. When it does not the P1218 will reset
I have seen both of these codes many times & the repair is replacement of the fuel injection pump.