Poor Fuel Economy

SYMPTOM DESCRIPTION:

From an actual road test the measured MPG is noticeably lower than expected. At one time the fuel economy for this vehicle was at a greater average than current measurement.




POSSIBLE CAUSE ACTION

Improper fuel ^ Drain fuel tank, flush system,
and fill with proper fuel. Change
fuel filter.






Incorrect injection pump to ^ Check and/or Adjust
engine timing injection pump timing.






Damaged or restricted injector ^ Clean or replace injector
nozzle nozzles.





Clogged or restricted fuel ^ Replace fuel filter.
filter





Fuel injection sequence ^ Check fuel injection lines
does not correspond with for proper routing.
firing order






Low idle speed setting ^ Adjust low idle speed.
out of adjustment






Malfunctioning KSB valve/ ^ Check KSB valve function.
injection pump If KSB valve is found to
be defective, replace injection
pump. Fuel Injection Pump Replacement

^ If injection pump is malfunctioning
or will not adjust properly, replace as
a unit. Fuel Injection Pump Replacement




Governor out of adjustment ^ Do Not attempt to adjust the governor,
because the injection pump and/or engine
warranty may be voided if any of the seals
have been tampered with or removed. Replace
injection pump as a unit, or have a certified
diesel pump repair facility adjust the governor.