Fuel System: Overview Dodge Challenger III рестайлинг

1. Remove the fuel pump relay from the Power Distribution Center (PDC). Refer to «FUSE LOCATIONS AND TYPES, SPECIFICATIONS»(ref-489279-S08493965412012072600000) . A relay location label can also be found on the underside of the PDC cover.
2. Start and run the engine until it stalls.
3. Attempt restarting engine until it will no longer run.
4. Turn ignition key to the OFF position.
5. Return fuel pump relay to the Power Distribution Center (PDC).

Note. After servicing the fuel system, one or more Diagnostic Trouble Codes (DTC's) may have been stored in the Powertrain Control Module (PCM) memory due to disconnecting the fuel pump module circuit. A diagnostic scan tool must be used to erase a DTC.

DESCRIPTION

The fuel pressure regulator is integrated with the auxiliary fuel pump module and is not serviced separately. The auxiliary fuel pump module must be replace if the fuel pressure regulator is to be replaced.

For auxiliary fuel pump module removal. Refer to MODULE, FUEL PUMP, REMOVAL .

The fuel level sending units and sensors are integrated with both the main fuel pump module and the auxiliary fuel pump module and are not serviced separately. The appropriate fuel pump module must be replace if either fuel level sending unit is to be replaced.

For fuel pump module removal. Refer to MODULE, FUEL PUMP, REMOVAL .

MODES OF OPERATION

As input signals to the PCM change, the PCM adjusts its response to output devices. For example, the PCM must calculate a different injector pulse width and ignition timing for idle than it does for Wide Open Throttle (WOT). There are several different modes of operation that determine how the PCM responds to the various input signals.

The multi-port fuel injection systems has the following modes of operation

1. Ignition switch ON (Zero RPM)
2. Engine start-up
3. Engine warm-up
4. Cruise
5. Idle
6. Acceleration
7. Deceleration
8. Wide-Open-Throttle
9. Ignition switch OFF

Within these modes of operation are two different functions, OPEN LOOP and CLOSED LOOP.

During OPEN LOOP operation the PCM receives input signals and responds according to preset PCM programming. Inputs from the upstream and downstream heated oxygen sensors (O2S) are not monitored during OPEN LOOP operation, except for heated O2S sensor diagnostics (they are checked for shorted conditions at all times).

During CLOSED LOOP operation the PCM monitors the inputs from the upstream and downstream heated O2S sensors. The upstream heated oxygen sensor input tells the PCM if the calculated injector pulse width resulted in the ideal air-fuel ratio of 14.7 to one. By monitoring the exhaust oxygen content through the upstream heated oxygen sensor, the PCM can fine tune injector pulse width. Fine tuning injector pulse width allows the PCM to achieve optimum fuel economy combined with low emissions.

For the PCM to enter CLOSED LOOP operation, the following must occur

1. Engine coolant temperature must be over 35°F (1.7°C). If the coolant is over 35°F (1.7°C) the PCM will wait 38 seconds. If the coolant is over 50°F (10°C) the PCM will wait 15 seconds. If the coolant is over 167°F (75°C) the PCM will wait 3 seconds. For other temperatures the PCM will interpolate the correct waiting time.
2. O2S sensor must read either greater than 0.745 volts or less than 0.29 volt.

OPEN LOOP operation is used for engine start-up (crank), engine warm-up, deceleration with fuel shutoff and wide open throttle. Under most conditions, acceleration, deceleration (with A/C on), idle and cruise modes, with the engine at operating temperature occur in CLOSED LOOP operation.

OPERATION

The PCM can test many of its own input and output circuits. If the PCM senses a fault in a major system, the PCM stores a Diagnostic Trouble Code (DTC) in memory.

For DTC information see On-Board Diagnostics. Refer to MODULE, POWERTRAIN CONTROL, DESCRIPTION .

The intake manifold features a dual shaft Short Runner Valve (SRV) system to maximize both low end torque and peak power. The SRV is bolted to the rear of the intake manifold and can be service separately from the manifold.

The SRV system operates under Wide Open Throttle conditions to maximize engine performance. When activated by the PCM, the SRV actuates a mechanical linkage to redirect the intake air flow to eight short runners. The PCM looks for a signal feedback when the actuator is activated. If the signal feedback is not present, the PCM sets the DTC.

Scheme 1

Scheme 2

Scheme 3

1. Disconnect the negative battery cable (1).
2. Remove the intake manifold and throttle body as an assembly. Refer to «MANIFOLD, INTAKE, REMOVAL»(ref-489304-S37202509642012072600000) or «MANIFOLD, INTAKE, REMOVAL, 5.7L»(ref-489305-S17410474082012072600000) or «MANIFOLD, INTAKE, REMOVAL»(ref-489306-S15645745872012072600000) .
3. Remove the Short Runner Valve (SRV) actuator retaining bolts (1) and remove the SRV actuator (2). NOTE: When the SRV actuator is removed, a new rubber O-ring seal must be installed. The old O-ring cannot be reused.
4. Remove and discard the SRV actuator rubber O-ring seal (1).