hello i was driving my ram about 25 mph and lost power and costed for away and started back up then my check e lite came on i check the code and got the code po121 witch is a apps it has 197k on the motor it had a injector pump replace at 90k should i reset the sensor first before i replace the sensor ? the sensor is very high . i also read about a vp44 my i ask what that is , thanks for any help.

 

vp44 = injection pump,

i would replace the apps if its doing that