Diagnostic Test

1. Visually and physically inspect the fuel delivery system for external leaks and damage.

   Is the system leaking or damaged?

   Yes 

   • Repair or replace as necessary.
   • Perform the PCM VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .

   No 

   • Go to step  2

Fig 1: Fuel Line Adapters/Fitting

Courtesy of CHRYSLER LLC

1. Turn the ignition off.
   WARNING: The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting, or line, the fuel system pressure must be released. Failure to follow these instructions can result in possible serious or fatal injury.
2. Disconnect the frame rail fuel supply line connector between the fuel supply line and the fuel rail.
3. Install the appropriate Fuel Line Adapters / Fitting from the Gas and Diesel Fuel Pressure/Decay Tester 8978A.

   Proceed 

   • Go to step  3

Fig 2: Identifying Fuel Pressure Gauge Assembly

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1. Connect the Gas and Diesel Fuel Pressure/Decay Tester 8978A, Fuel Inlet Hose (1) and Fuel Outlet Hose (2) to the Fuel Line Adapters / Fitting.
2. Connect special tool Drain Extension Hose 535680 (3) to the Fuel Pressure Gauge Assembly Drain Hose (5).
3. Connect Reservoir Assembly 534960 (4) to Drain Extension Hose 535680 (3).
   WARNING: To reduce the risk of fire and possible serious or fatal injury, place Reservoir Assembly 534960 (4) on the floor and out of the way so that it is not a trip hazard.

   Proceed 

   • Go to step  4

Fig 3: Checking Fuel Pressure

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Perform the following procedure to purge air from the system:

• Open the Fuel System Isolation Valve (1).
• Close the Flow Test Valve (2).
• Ignition on, engine not running.
• With the scan tool, actuate the fuel pump.
• Open the Flow Test Valve (1) for 10 seconds, then close the Valve.
• CAUTION: Stop All Actuations. 
• Turn the ignition off.
• Disconnect, empty and then reconnect the Reservoir Assembly.

1. Turn the ignition on, wait five seconds, turn the ignition off and then wait one minute before proceeding.
2. Read the Fuel Pressure Gauge (3) and record the reading. Non SRT-4  fuel pressure specification is 407 kPa +/- 34 kPa (59 psi +/- 5 psi). SRT-4  fuel pressure specification is 552 kPa +/- 34 kPa (80 psi +/- 5 psi).

   Is the fuel pressure within specifications?

   Yes 

   • Go to step  5

   No 

   • See Non-DTC Diagnostics/Driveability - Gas - Diagnosis and Testing  and perform the CHECKING THE FUEL DELIVERY SYSTEM diagnostic procedure.

Fig 4: Checking Fuel Delivery System Output

Courtesy of CHRYSLER LLC

1. Ignition on, engine not running.
2. With the scan tool, actuate the fuel pump.
3. Open the Flow Test Valve (1) for 20 seconds, then close the Valve.
   CAUTION: Stop All Actuations.
4. Turn the ignition off.
5. Measure the amount of fuel in the Reservoir Assembly (2). The fuel output specification is ml/s x 20 seconds = fuel flow in ml.