Medium and Heavy Trucks
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Hi my name is***** will be glad to help. What are you getting for fuel pressure? If the fuel pressure is good and you have no other symptoms or fault codes then it is possible you could have a TRS or SRS sensor problem where the ECM is losing engine speed signal or a possible ECM problem. Let me know what you have for fuel pressure.
Fuel pressure specs
You can upload it to you tube and post the link...
Ok, If you have a new pump, there is no restrictions or leaks sucking air between the tank and pump then check the return check valve at the rear of the head. It is a 90 degree fitting coming out of the back of the head. another potential cause is failed injector o rings.
Try applying air pressure to the fuel rail to listen for leaks
I see you also already bypassed the fuel lines by running a direct line and there was no change indicating the problem is between the pump and return side. I have also heard of faulty pumps right out of the box so lets not rule that completely out as a possibility.
Check your trs and srs sensors and harness. If ok try a test ECM. a lot of times when odd things happen with no codes it is an ECM issue. Do you have a sister truck you can swap ECM with for test purposes?
Thanks for the update. Where are you disconnecting the air at the turbo? The filter inlet or the turbo outlet to the manifold? what year engine is this? EGR engine? VNT turbo?
Thanks for the update. So he disconnected the turbo line to the intake and the engine will not stall? sounds like a faulty turbo to me. Inspect and clean the turbo vanes.
Click here for the test procedures. Run through the tests and let me know what you get for the results
Flash code 39
Code s 147/2 — occurs if error in actual boost vs desired boost during Power Boost mode
operation is gr
eater than it should be. This fault will illuminate the CEL/AWL for the duration
of the fault being active.
Check the VNT vanes and actuator for sticking and proper operation. The turbo is variable boost by the vane position. If they are sticking from carbon or the actuator is faulty then the turbo could be stuck in full boost etc
Check the actuator movement and verify the rod can move fully in both directions and the vanes in the turbo ar not sticking. See the link I posted for the you tube video for its operation. Pressure test the intake piping and charge air cooler.
Basic checks for all Series 60 EGR engines require the following tools:1,000 Ohm resistor (low watt)DDR suite 9 or DDDL version 6.0 or higherVolt Ohm MeterPressure gage 0–200 psi (0-1378 kPa)Pressure gage 0–100 psi (0-689 kPa)Regulated shop air pressure (10 psi)Section 20.18.1Check EGR ControlsPerform the following steps to check the EGR system components.Turn ignition ON.Plug in DDR/DDDL.Any EGR-related codes (except Flash Code 39)?If codes were logged, troubleshoot the codes as necessary.If no codes were logged (besides Code 39), proceed to step 4 .Inspect system for any air leaks in the exhaust, EGR, or intake system (including charge-air-cooler).If leaks were detected, repair as necessary.If no leaks are present, go to step 5 .Check Delta P counts on DDR/DDDL (counts should be between 86 and 118).Note: The ignition is set to the ON position and the engine is not running.If the counts were between 86 and 118, refer to "20.18.2 Check VPOD Input Pressure" .If the counts were not between 86 and 118, perform Delta P sensor auto calibration using DDDL. Retest, if Delta P sensor counts are not between 86 and 118, replace the Delta P sensor, refer to "20.18.7 Check for Active Codes" . If the counts are between 86 -118, then verify repair.Section 20.18.2Check VPOD Input PressureFollow these steps to check VPOD input pressure: Measure the vehicle air supply pressure to VPOD input pressure to port 1; ensure it is between 102 – 188 psi. (703 – 1296 kPa).If the supply pressure is not between 102 – 188 psi (703 – 1296 kPa), troubleshoot the vehicle air system until that result is obtained.If the supply pressure is between 102 – 188 psi (703 – 1296 kPa ), refer to "20.18.3 Check VPOD Output Pressure" .Section 20.18.3Check VPOD Output PressureFollow these steps to check VPOD output pressure: Disconnect the air hose from the VNT (Variable Nozzle Turbocharger) actuator.Install a 100 psi pressure gauge (accurate to within 1.4 kPa [0.2 psi]) at the outlet of the VNT hose.Using the DDR/DDDL, activate cavity E-4 (VNT) duty cycle and monitor the output pressure from the VPOD.Test: Activate the cavity to 50 % duty cycle: Pressure = 310 ± 14 kPa (45 ± 2 psi).If the VPOD readings are as listed above, refer to "20.18.6 Check EGR Valve" .If the results in this step cannot be attained, or if the VPOD leaks when activated replace the VPOD.If the VPOD has been replaced, refer to "20.18.4 Check VPOD Supply Voltage" .Section 20.18.4Check VPOD Supply VoltageThe following checks should be performed for the VPOD supply voltage:Check VPOD label to determine if it is + 12V or + 24V compatible.Unplug VPOD mating connector. A 1,000 Ohm resistor is needed for the next step. Insert the resistor between cavity 1 and 3 for ease of checking with the VOM.
Also, Compare key on engine off values for the boost press and barometric press sensors. They should be within .4 psi of each other and pressure test your entire boost intake piping, should not leak more than 5 psi in 15 seconds. Also check the delta press sensor tubes for plugging.
Thanks for the info. The Baro pressure sensor or harness could be part of the problem if everything else checks good... Inspect the harness and swap out the sensor. Let me know
And the turbo and actuator have been confirmed good?
Click on this link for the operation and technical manual that will explain the EGR and VNT turbo operation with the three modes ( Boost, EGR, Brake mode)
operation and troubleshooting