
TEST ACTION APPLICABILITY
8 Ignition Off
Inspect the Chassis Fuel Supply Line to engine for a kink or restriction.
Is the Line kinked or restricted?ENGINE - 2.4L I-4
DOHC and/or EN-
GINE - 3.3L V6
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.8L V6
Ye s®Release the Fuel Pressure. Repair the Fuel Line as necessary.
Perform Powertrain Verification Test VER-2A.
No®Go To 9
9 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Connect a Fuel Pressure Adapter and Gauge to Supply Line between Tank/Filter.
Turn ignition on.
With the DRB, actuate the Fuel System test.
Is the Fuel Pressure at least 5 psi higher than previously recorded pressure?ENGINE - 2.4L I-4
DOHC and/or EN-
GINE - 3.3L V6
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.8L V6
Ye s®Release the Fuel Pressure. Replace the Fuel Filter.
Perform Powertrain Verification Test VER-2A.
No®Go To 10
10 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Connect a Fuel Pressure Adapter and Gauge to Supply Line between Tank/Filter.
Turn ignition on.
With the DRB, actuate the Fuel System test.
Is Fuel Pressure at least 5 psi higher than previously recorded pressure?ENGINE - 2.4L I-4
DOHC and/or EN-
GINE - 3.3L V6
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.8L V6
Ye s®Test Complete.
No®Release the Fuel Pressure. Replace the Fuel Pump and Regulator
Assembly.
Perform Powertrain Verification Test VER-2A.
11 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Relieve the Fuel Pressure.
Tee-in Fuel Pressure Gauge into the Fuel Supply Hose using Tool #6433.
Turn ignition on.
With the DRB, actuate the ASD Fuel System test.
Is the Fuel Pressure between 43 and 53 psi?ENGINE - 3.0L V6
Ye s®Go To 12
No®Go To 15
12 Ignition Off
Note: Make sure the Gear Lever is in neutral, and the Park Brakes engaged.
Start the engine.
Monitor the Fuel Pressure Gauge in the next step.
While monitoring the pressure, momentarily snap Throttle wide open raising RPM to
above 3000.
Did the fuel pressure drop below 35 psi at all?All
Ye s®Go To 13
No®Test Complete.
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DRIVEABILITY
* CHECKING FUEL DELIVERY ÐContinued
ProCarManuals.com

TEST ACTION APPLICABILITY
13 Ignition Off
Inspect the Chassis Fuel Supply Line to the engine for a kink or restriction.
Is the line kinked or restricted?All
Ye s®Release the fuel pressure. Repair the Fuel Line as necessary.
Perform Powertrain Verification Test VER-2A.
No®Go To 14
14 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Remove the Fuel Pressure Gauge from the Fuel Rail.
Adjust a shop air hose to 40 psi.
Remove the Fuel Filter.
Using shop air, inspect the Fuel Filter passage by attempting to blow air through
inlet.
Is the Fuel Filter restricted?All
Ye s®Replace the Fuel Filter.
Perform Powertrain Verification Test VER-2A.
No®Replace the Fuel Pump and Regulator Assembly.
Perform Powertrain Verification Test VER-2A.
15 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Relieve the Fuel Pressure.
Tee-in Fuel Pressure Gauge into the Fuel Supply Hose using Tool #6433.
Turn Ignition On.
With the DRB, actuate the ASD Fuel System test.
Record the Fuel Pressure reading.
Is the Fuel Pressure above 53 psi?ENGINE - 3.0L V6
Ye s®Go To 16
No®Go To 18
16 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Remove the Fuel Pressure Gauge from the Fuel Rail.
Remove the Fuel Return Line between the Fuel Tank and Filter.
Adjust a shop air hose to 40 psi.
Using shop air, inspect the Fuel Line by attempting to blow air through it.
Is the Fuel Return Line restricted?All
Ye s®Replace the Fuel Return Line.
Perform Powertrain Verification Test VER-2A.
No®Go To 17
17 If there are no potential causes remaining, the Fuel Pressure Regulator is assumed
to be defective.
View repair options.All
Repair
Replace the Fuel Pressure Regulator.
Perform Powertrain Verification Test VER-2A.
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DRIVEABILITY
* CHECKING FUEL DELIVERY ÐContinued
ProCarManuals.com

TEST ACTION APPLICABILITY
18 Ignition Off
Inspect the Chassis Fuel Supply Line to engine for a kink or restriction.
Is the Fuel Line kinked or restricted?ENGINE - 3.0L V6
Ye s®Release the Fuel Pressure. Repair the Fuel Line as necessary.
Perform Powertrain Verification Test VER-2A.
No®Go To 19
19 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Install Fuel Pressure Gauge between Fuel Tank and Fuel Filter.
Key on.
With the DRB, actuate the ASD Fuel System test.
Is fuel pressure at least 5 psi higher than the previously recorded pressure?ENGINE - 3.0L V6
Ye s®Release the Fuel Pressure. Replace the Fuel Filter.
Perform Powertrain Verification Test VER-2A.
No®Go To 20
20 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Install Fuel Pressure Gauge between Fuel Tank and Fuel Filter.
Key on.
With the DRB, actuate the ASD Fuel System test.
Is fuel pressure at least 5 psi higher than the previously recorded pressure?ENGINE - 3.0L V6
Ye s®Test Complete.
No®Release the Fuel Pressure. Replace the Fuel Pump and Regulator
Assembly.
Perform Powertrain Verification Test VER-2A.
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DRIVEABILITY
* CHECKING FUEL DELIVERY ÐContinued
ProCarManuals.com

Symptom:
* CHECKING THE FUEL SYSTEM
POSSIBLE CAUSES
FUEL PUMP GROUND CIRCUIT OPEN
FUEL PUMP GROUND CIRCUIT OPEN
FUEL PUMP RELAY FUSED B(+) CIRCUIT OPEN
FUEL PUMP RELAY FUSED B(+) CIRCUIT OPEN
FUEL PUMP RELAY OUTPUT CIRCUIT OPEN
FUEL PUMP RELAY OUTPUT CIRCUIT OPEN
FUEL FILTER DEFECTIVE
FUEL FILTER DEFECTIVE
FUEL PUMP DEFECTIVE
FUEL PUMP DEFECTIVE
FUEL PUMP RELAY
FUEL PUMP RELAY
IN-TANK FUEL PRESSURE REGULATOR DEFECTIVE
IN-TANK FUEL PRESSURE REGULATOR DEFECTIVE
THROTTLE POSITION SENSOR DEFECTIVE
FUEL FILTER DEFECTIVE
FUEL FILTER DEFECTIVE
FUEL INLET STRAINER DEFECTIVE
FUEL INLET STRAINER DEFECTIVE
FUEL PUMP MODULE DEFECTIVE
FUEL PUMP MODULE DEFECTIVE
FUEL SUPPLY LINE DEFECTIVE
FUEL SUPPLY LINE DEFECTIVE
FUEL TUBE RESTRICTED
FUEL TUBE RESTRICTED
POWERTRAIN CONTROL MODULE DEFECTIVE
POWERTRAIN CONTROL MODULE DEFECTIVE
THROTTLE CABLES DEFECTIVE
THROTTLE CABLES DEFECTIVE
THROTTLE POSITION SENSOR DEFECTIVE
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TEST ACTION APPLICABILITY
1Note: Ensure the SKIM has proper communication and that there are no
SKIM DTC's present before continuing.
Ignition Off.
Ensure the Throttle Cables are not holding the Throttle open.
Is the Throttle held open?ENGINE - 3.0L V6
Ye s®Repair condition that holds the Throttle Body open.
Perform Powertrain Verification Test VER-1A.
No®Go To 2
2 Ignition On, Engine Not Running
With the DRB, actuate the Fuel System and check for Fuel Pump operation at the
Fuel Tank.
Is the Fuel Pump operating?ENGINE - 3.0L V6
Ye s®Go To 3
No®Go To 13
3 Ignition On, Engine Not Running
With DRB, read Throttle Position Sensor voltage.
Is the voltage above 1.5 volts?ENGINE - 3.0L V6
Ye s®Disconnect the TP Sensor Conn. Replace Throttle Position Sensor.
Perform Powertrain Verification Test VER-1A.
No®Go To 4
4 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Relieve Fuel pressure.
Install a Fuel Pressure Gauge to the Fuel Rail.
Note: The Fuel Tank must be at least 1/4 full for the following tests.
Ignition On, Engine Not Running.
With the DRB, actuate the Fuel System.
Read the Fuel Pressure Gauge.
Fuel pressure should be 43 to 53 psi for Gasoline.
Is the Fuel pressure above the specification ?ENGINE - 3.0L V6
Ye s®Go To 5
No®Go To 8
5 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release the Fuel pressure.
Inspect Fuel Filter for a restriction.
Is there a restriction?ENGINE - 3.0L V6
Ye s®Replace the Fuel Filter.
Perform Powertrain Verification Test VER-1A.
No®Go To 6
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STARTING
* CHECKING THE FUEL SYSTEM ÐContinued
ProCarManuals.com

TEST ACTION APPLICABILITY
6 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release the Fuel pressure.
Inspect Fuel Filter for a restriction.
Is there a restriction?ENGINE - 3.0L V6
Ye s®Go To 7
No®Replace the Fuel Pressure Regulator.
Perform Powertrain Verification Test VER-1A.
7 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release the Fuel pressure.
Inspect Fuel Return Tube for restriction between fuel Filter and Fuel Pump Module.
Is there a restriction?ENGINE - 3.0L V6
Ye s®Replace restricted Fuel Tube.
Perform Powertrain Verification Test VER-1A.
No®Test Complete.
8 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Relieve Fuel pressure.
Tee-In a Fuel Pressure Gauge into the Fuel Hose using tool #6433.
Note: The Fuel Tank must be at least 1/4 full for the following tests.
Ignition On, Engine Not Running.
With the DRB, actuate the Fuel System.
Read the Fuel Pressure Gauge.
Fuel pressure should be 43 to 53 psi for Gasoline.
Is the Fuel pressure below the specification ?ENGINE - 3.0L V6
Ye s®Go To 9
No®Test Complete.
9 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release Fuel pressure.
Remove adapter 6631 and reinstall Fuel Line.
Install adapter 6631 between Fuel Pump and Fuel Filter.
Connect Fuel Pressure Gauge to adapter 6631.
Key on.
With the DRB, actuate Fuel System.
Is the fuel pressure at least 2 psi higher than the previous reading?ENGINE - 3.0L V6
Ye s®Replace the Fuel Filter.
Perform Powertrain Verification Test VER-1A.
No®Go To 10
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STARTING
* CHECKING THE FUEL SYSTEM ÐContinued
ProCarManuals.com

TEST ACTION APPLICABILITY
10 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release Fuel pressure.
Remove the Fuel Pump Module.
Inspect the Fuel Pump Inlet Strainer.
Is the Inlet Strainer plugged?ENGINE - 3.0L V6
Ye s®Replace the Fuel Inlet Strainer.
Perform Powertrain Verification Test VER-1A.
No®Go To 11
11 Record the Fuel Pressure Gauge reading.
Ignition key off.
Warning: The Fuel System must be opened and may be under high pressure.
Release Fuel pressure.
Remove the Fuel Pressure Gauge.
Remove Fuel Pressure Gauge Adapter 6433 and reconnect Fuel Line to Fuel Rail.
Install adapter 6631 between Fuel Filter Outlet and Chassis Fuel Supply Tube.
Connect Fuel Pressure Gauge to adapter 6631.
Ignition On, Engine Not Running.
With DRB, actuate the ASD Fuel System.
Record the Fuel Pressure Gauge reading.
Compare this reading with the previous reading.
Is the fuel pressure at least 2 psi higher than the previous reading?ENGINE - 3.0L V6
Ye s®Repair restriction in Chassis Fuel Supply Line between Fuel
Filter and Fuel Rail.
Perform Powertrain Verification Test VER-1A.
No®Go To 12
12 If there are no potential causes remaining, the Fuel Pump Module is assumed to be
defective.
View repair options.ENGINE - 3.0L V6
Repair
Replace Fuel Pump Module.
Perform Powertrain Verification Test VER-1A.
13 Ignition On, Engine Not Running
With DRB, read Throttle Position Sensor voltage.
Is the voltage above 1.5 volts?ENGINE - 3.0L V6
Ye s®Disconnect the TP Sensor Conn. Replace Throttle Position Sensor.
Perform Powertrain Verification Test VER-1A.
No®Go To 14
14 Ignition Off.
Disconnect the Fuel Pump Harness Connector.
Note: Check connectors - Clean/repair as necessary.
Caution: It is critical that the Fuel Pump Connector has a clean and tight
connection.
With an Ohmmeter, measure the Fuel Pump Ground Circuit.
Is the resistance below 5.0 ohms?ENGINE - 3.0L V6
Ye s®Go To 15
No®Repair the open Fuel Pump Ground Circuit.
Perform Powertrain Verification Test VER-1A.
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* CHECKING THE FUEL SYSTEM ÐContinued
ProCarManuals.com

TEST ACTION APPLICABILITY
20 Ignition On, Engine Not Running
With the DRB, actuate the Fuel System and check for Fuel Pump operation at the
Fuel Tank.
Is the Fuel Pump operating?ENGINE - 2.0L,
2.4L I-4 DOHC
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.3L V6
and/or ENGINE -
3.8L V6
Ye s®Go To 21
No®Go To 30
21 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Relieve Fuel pressure.
Install a Fuel Pressure Gauge to the Fuel Rail.
Note: The Fuel Tank must be at least 1/4 full for the following tests.
Ignition On, Engine Not Running.
With the DRB, actuate the Fuel System.
Read the Fuel Pressure Gauge.
For 3.3 liter engines fuel pressure should be 50 to 60 psi, and for all other engines fuel
pressure should be 43 to 53 psi.
Is the Fuel pressure above the specification ?ENGINE - 2.0L,
2.4L I-4 DOHC
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.3L V6
and/or ENGINE -
3.8L V6
Ye s®Go To 22
No®Go To 25
22 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release the Fuel pressure.
Inspect Fuel Filter for a restriction.
Is there a restriction?ENGINE - 2.0L,
2.4L I-4 DOHC
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.3L V6
and/or ENGINE -
3.8L V6
Ye s®Replace the Fuel Filter.
Perform Powertrain Verification Test VER-1A.
No®Go To 23
23 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release the Fuel pressure.
Inspect Fuel Filter for a restriction.
Is there a restriction ?ENGINE - 2.0L,
2.4L I-4 DOHC
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.3L V6
and/or ENGINE -
3.8L V6
Ye s®Go To 24
No®Replace the Fuel Pressure Regulator.
Perform Powertrain Verification Test VER-1A.
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STARTING
* CHECKING THE FUEL SYSTEM ÐContinued
ProCarManuals.com