Interview the operator to verify the complaint
Refer to the Driveability/Low Power – Customer Complaint Form at the end of the TS section.
Follow the instructions on the form before continuing with this tree.
Fuel leak
Check the fuel lines, fuel connections, and fuel filters for leaks. Check the fuel lines to the supply
tanks. Refer to the OEM service manual.
Fuel economy expectations are not reasonable
Verify what factors compose the operator’s expectations. Run a VENMS® simulation for
automotive applications to determine the expected fuel economy or perform a trial run to establish the actual fuel economy. Refer to the OEM service manual.
Operator technique is not correct
Explain correct engine operation to the operator. Refer to Section 1 in the Owners Manual or
Operation and Maintenance Manual of the engine being serviced.
Lubricating oil level is above specification
Check the oil level. Verify the dipstick calibration and oil pan capacity. Fill the system to the specified level. Refer to Procedure 007-009 in Section 7.
Refer to Procedure 007-037 in Section 7.
Lubricating oil does not meet specifications for operating conditions
Change the oil and filters. Refer to Procedure 007-037 in Section 7. See the Owners Manual and/
or Operation and Maintenance Manual for the engine being serviced for oil specifications.
Hubometer or odometer is miscalibrated
Check the hubometer and odometer calibrations. Calibrate or replace the hubometer or odometer, if
necessary. Calculate fuel consumption with new mileage figures.
Electronic fault codes active or high counts of inactive fault codes
View and troubleshoot the fault codes with INSITETM electronic service tool. Refer to the
Troubleshooting and Repair Manual, CM21 00 and CM2150 Electronic Control System, Bulletin
4021570.
Programmable parameters or selected features are not correct
Check the programmable parameters and the selected features with an electronic service tool.
Set the parameters and features again, if necessary. Refer to Procedure 019-078 in Section
19. This procedure is in the Troubleshooting and Repair Manual, CM2100 and CM2150 Electronic
Control System, Bulletin 4021570.
Electronic control module (ECM) calibration is malfunctioning
Verify the ECM calibration is correct. Check the calibration revision history for applicable fixes to
the calibration stored in the ECM. Refer to the calibration history spreadsheet ecm_calibration_rev_history.xlson QuickServem Online or the INCALm CD-ROM. Compare the
calibration stored in the ECM with the engine rating and Control Parts List (CPL), Bulletin 4021328. If necessary, calibrate the ECM. Refer to Procedure 019-032 in Section 19.This procedure is in Troubleshooting and Repair Manual, CM2100 and CM2150 Electronic Control System, Bulletin 4021570.
Engine idle or PTO time is excessive
Check the idle or PTO time with INSITETM electronic service tool. Low oil and coolant temperatures can be caused by long idle time (greater than 10 minutes).
Aftertreatment System active regeneration time is excessive
Check the aftertreatment system trip information with INSITETM electronic service tool. Low duty
cycle applications can possibly require more active regeneration time to keep the aftertreatment
system functioning correctly. Change the vehicle route and/or duty cycle to increase the load on the
engine in order to decrease the amount of active regeneration time.
Auxiliary devices using fuel from vehicle•s fuel supply tank(s)
Check the fuel consumption of the auxiliary devices. Refer to the OEM service manual.
Equipment and environmental factors are affecting fuel consumption
Consider ambient temperatures, wind, tire size, axle alignment, routes, and use of aerodynamic
aids when evaluating fuel consumption.
Vehicle parasitics are excessive
Check the vehicle for brakes dragging, transmission malfunction, cooling fan operation
cycle time, and engine-driven units. Refer to the OEM service manual.
Drivetrain is not correctly matched to the engine
Check for correct gearing and drivetrain components. Refer to the OEM service manual.
Intake manifold pressure (boost) sensor or circuit is malfunctioning
Check the boost sensor and circuit. Compare the intake manifold pressure sensor reading in the
monitor mode using INSITE electronic service tool, to a manual pressure gauge. Refer to
Procedure 019-159 in Section 19.This procedure is in the Troubleshooting and Repair Manual,
CM21 00 and CM2150 Electronic Control System, Bulletin 4021570.
Vehicle speed sensor (VSS) or circuit is malfunctioning
Refer to the appropriate electronic service tool manual. If the monitor shows speed, check the
sensor and circuit. Refer to Procedure 019-090 in Section 19. Refer to Procedure 019-091 in Section
19. These procedure are in the Troubleshooting and Repair Manual, CM2100 and CM2150
Electronic Control System, Bulletin 4021570.
Vehicle speed sensor (VSS) tampering has occurred
Check the vehicle speed sensor and circuit for tampering. Check for Fault Code 242. Repair the
circuit as necessary. Refer to Procedure 019-090 in Section 19. Refer to Procedure 019-091 in
Section 19. These procedures are in the Troubleshooting and Repair Manual, CM21 00 and
CM2150 Electronic Control System, Bulletin 4021570.
Air intake or exhaust leaks
Check for loose or damaged piping connections and missing pipe plugs. Check the turbocharger
and exhaust manifold mounting. Refer to Procedure 010-024 in Section 10.
Charge-air cooler is restricted or leaking
Inspect the charge-air cooler for air restrictions or leaks. Refer to Procedure 010-027 in Section 10.
Air intake system restriction is above specification
Check the air intake system for restrictions. Clean or replace the air filter and inlet piping as
necessary. Refer to Procedure 010-031 in Section 10.
Exhaust system restriction is not within specification
Check the exhaust system for restrictions. Refer to Procedure 011-009 in Section 11.
Fuel grade is not correct for the application or the fuel quality is poor
Operate the engine from a tank of high quality fuel. Refer to the Owners Manual and/or Operation and Maintenance Manual for the engine being serviced for fuel specifications.
Overhead adjustments are not correct
Measure and adjust the overhead settings. Refer to Procedure 003-004 in Section 3.
lnjector(s) are malfunctioning
Perform diagnostics to find the damaged injector (s). Replace the injector(s) as necessary. Refer to
Procedure 014-008 in Section 14. Refer to Procedure 006-026 in Section 6.
Internal engine damage
Analyze the oil and inspect the filters to locate an area of probable damage. Refer to Procedure
007-048 in Section 7. Refer to Procedure 007-083 in Section 7.
