Dodge ZB 2005 Service Manual page 1194

P0171-1/1 FUEL SYSTEM LEAN —
TEST
4 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.
Remove the Fuel Pump Module and inspect the Fuel Inlet Strainer.
Is the Fuel Inlet Strainer plugged?
Yes → Replace the Fuel Pump Inlet Strainer.
→ Go To 5
No
5 If there are no possible causes remaining, view repair.
Repair
6 Turn the ignition off.
NOTE: Wait a minimum of 10 minutes to allow the O2 Sensor and Exhaust
System to cool down before continuing the test.
Ignition on, engine not running.
With the DRBIII , read the O2 Sensor voltage.
Is the voltage above 4.5 volts?
Yes → Go To 7
→ Go To 13
No
7 Turn the ignition off.
NOTE: Wait a minimum of 10 minutes to allow the O2 Sensor to cool down
before continuing the test.
Ignition on, engine not running.
With the DRBIII , actuate the O2 Heater Test.
With the DRBIII , monitor O2 Sensor voltage for at least 2 minutes.
Does the voltage stay above 4.5 volts?
Yes → Replace the O2 Sensor.
→ Go To 8
No
8 With the DRBIII , read TP Sensor voltage.
NOTE: The throttle must be against the stop.
Is the voltage 0.92 of a volt or less with the Throttle closed?
Yes → Go To 9
→ Check for a binding throttle condition. If OK, replace the Throttle
No
9 With the DRBIII , read the TP Sensor voltage.
While monitoring the DRBIII , slowly open and close the throttle.
Does the voltage increase and decrease smoothly?
Yes → Go To 10
→ Replace the Throttle Position Sensor.
No
ACTION
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
DRIVEABILITY - GAS
Continued
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APPLICABILITY
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