DD15 Troubleshooting – Section 10.2 Low Power Troubleshooting Chart

There are three basic checks that should be performed:‪

Check for active/historic codes. All causes need to be checked once the fault is identified. Record faults on the Application For Adjustment (AFA) claim, if there is to be a claim.
Check the DDEC parameters, progressive shift settings, torque limiting values, and injector codes. Are they correct? Is proper rating applied? If vehicle is new, is it spec'd correctly?
Check that the dyno-measured power is within Detroit Diesel specifications as Listed in Table "Minimum Acceptable Wheel HP" for minimum acceptable wheel HP data. Record data on AFA claim.

Note: Service information letter instructions published following the date of this document take precedence.

Possible causes of low power and symptoms are listed in Table "Low Power Troubleshooting Chart" .‪

Possible Causes‪	Symptoms‪
Possible Causes‪	Loss of Power‪	Misfires‪	Poor‪ Acceleration‪	Erratic Idle‪	Engine Dies‪	Black Smoke‪	Excessive Oil‪ Consumption‪
Fuel Filter Restriction‪	X‪	X‪	X‪	X‪	X‪	—‪	—‪
Fuel Shut-Off Valve not Open‪	X‪	X‪	X‪	X‪	X‪	—‪	—‪
Air in the Fuel‪	X‪	X‪	X‪	X‪	X‪	—‪	—‪
Faulty Injector(s)‪	X‪	X‪	X‪	X‪	X‪	X‪	—‪
Faulty Turbocharger‪	X‪	—‪	X‪	—‪	—‪	X‪	X‪
EGR Valve*‪	X‪	—‪	X‪	X‪	—‪	X‪	—‪
Delta P Sensor or Plugged Lines*‪	X‪	—‪	X‪	X‪	—‪	X‪	—‪
Charge Air Cooler Leak‪	X‪	—‪	X‪	—‪	—‪	X‪	—‪
Intake or Exhaust Manifold Leak‪	X‪	—‪	X‪	—‪	—‪	X‪	—‪
Quality/Grade of Fuel‪	X‪	X‪	X‪	X‪	—‪	X‪	—‪
High Fuel Temperature - Above 130°F‪	X‪	—‪	X‪	—‪	—‪	—‪	—‪
Restricted Air Intake‪	X‪	—‪	X‪	—‪	—‪	X‪	—‪
Crankcase Overfilled‪	X‪	—‪	X‪	—‪	—‪	—‪	X‪
Faulty Fan Operation, Always On‪	X‪	—‪	X‪	—‪	—‪	—‪	—‪
Debris in Fuel Tank - Air Vent Plugged‪	X‪	X‪	X‪	X‪	X‪	—‪	—‪

Table 1. Low Power Troubleshooting Chart

EPA07 DD15 Troubleshooting Guide - DDC-SVC-MAN-0029

Generated on 10-13-2008