OBD Operation Summary for 6.7L Diesel - MotorCraftService.com
OBD Operation Summary for 6.7L Diesel - MotorCraftService.com OBD Operation Summary for 6.7L Diesel - MotorCraftService.com
General Description 6.7L Diesel EngineThe 6.7L is a V8 engine designed to meet customer expectations of high horsepower and torque with exceptionalfuel economy and low NVH. It must do this while meeting the tough emissions standards set by the EPA andCARB.Some of the technologies employed to meet these diverse criteria include a Variable Geometry Turbocharger(VGT), common rail fuel injection system, electronically controlled, cooled EGR, a diesel oxidation catalyst (DOC) ,Selective Catalytic Reduction catalyst (SCR), Diesel Exhaust Fluid (DEF) injection system, and a diesel particulatefilter (DPF).The system schematic on the next page shows the path of the air as it is compressed by the turbocharger, cooledby the air-to-coolant intercooler, and mixed with the cooled EGR gases. The state of this compressed and heatedair is sensed by the manifold absolute pressure (MAP) sensor just before it enters the cylinders and the twotemperature sensors that represent Charge Air Cooler Outlet temperature (CACT1) and EGR Cooler outlettemperature (EGRCOT). The exhaust gas pressure is measured by the exhaust backpressure (EP) sensor beforeit exits through the turbocharger. The exhaust after treatment system consists of a DOC, a SCR, a DPF and amuffler.An electronic, proportional valve controls EGR rates with an integral position sensor (EGRP). Flows aredetermined by valve position and the amount that backpressure exceeds boost pressure. An EGR throttle(EGRTP) is used for regeneration control as well as to optimize the boost pressure vs. backpressure levels.Fuel injection pressure is measured by the high-pressure fuel rail sensor (FRP). Injection pressure is controlled bythe high pressure pump and two regulating valves, a Pressure Control Valve (PCV), and a Fuel Metering Unit(MeUn), formerly known as Volume Control Valve (VCV).Engine speed (N) and crankshaft position are determined by the crankshaft position sensor (CKP) which senses a60 minus 2 tooth target wheel. Camshaft position is determined by the camshaft position sensor (CMP), whichsenses the profile of a multiple lobed camshaft.Atmospheric pressure is determined by the Barometric Pressure sensor (BARO) mounted internally in the EngineControl Module (ECM).During engine operation, the ECM calculates engine speed from the crankshaft position sensor. The ECMcontrols engine operation by controlling the piezo injector opening and closing times as well as the pressure atwhich the fuel is injected, thereby controlling fuel quantity and timing. Simultaneously, airflow is modulated bycontrolling the turbocharger vane position.Fuel quantity is controlled by injector “on time” (pulse width) and the fuel rail pressure. Desired engine speed isdetermined from the position of the accelerator pedal.FORD MOTOR COMPANY REVISION DATE: FEBRUARY 9, 2012 09.01.00.02-PAGE 8 OF 157
System Schematic 6.7L Chassis CertifiedFORD MOTOR COMPANY REVISION DATE: FEBRUARY 9, 2012 09.01.00.02-PAGE 9 OF 157
- Page 1 and 2: 2013 MY OBD System OperationSummary
- Page 3 and 4: Cam and Crank Sensor: .............
- Page 5 and 6: Introduction - OBD-II and EMDOBD-II
- Page 7: Comprehensive Component MonitorGlow
- Page 11 and 12: The dynamometer certified applicati
- Page 13 and 14: NON-METHANE HYDROCARBON (NMHC) CONV
- Page 15 and 16: OXIDES OF NITROGREN (NOx) CONVERTIN
- Page 17 and 18: Selective Catalyst Reduction Feedba
- Page 20 and 21: Misfire Monitor Operation:DTCsMonit
- Page 22 and 23: Fuel Rail Pressure ( FRP ) Rational
- Page 24 and 25: Fuel Temperature Sensor Circuit Che
- Page 26 and 27: Fuel Pressure Control Valve (PCV) M
- Page 28 and 29: Fuel Injector Driver Circuit Monito
- Page 30 and 31: Injector Code Missing/Invalid:Injec
- Page 32 and 33: Injection Timing / Injection quanti
- Page 34 and 35: Feedback control:Fuel Balancing Con
- Page 36 and 37: VoltageNominal Voltage Calibration:
- Page 38 and 39: EXHAUST GAS SENSOR MONITORAir-Fuel
- Page 40 and 41: The NOx sensor is primarily used to
- Page 42 and 43: percent O2P0133 (O2 slow response)
- Page 44 and 45: EXHAUST GAS RECIRCULATION (EGR) SYS
- Page 46 and 47: EGR Cooler/ECB Entry Conditions (Ov
- Page 48 and 49: EGR System Slow ResponseSlow respon
- Page 50 and 51: Mass Airflow Closed-loop Control Li
- Page 52 and 53: Note: this monitor also serves to m
- Page 54 and 55: Functional Overboost MonitoringThe
- Page 56 and 57: Threshold Underboost MonitoringThe
System Schematic <strong>6.7L</strong> Chassis CertifiedFORD MOTOR COMPANY REVISION DATE: FEBRUARY 9, 2012 09.01.00.02-PAGE 9 OF 157