Dodge ZB 2005 Service Manual page 1198

P0172-1/1 FUEL SYSTEM RICH —
TEST
1 NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
Ignition on, engine not running.
With the DRBIII , read DTCs and record the related Freeze Frame data.
NOTE: Any O2 Sensor, TPS, ECT, MAP, or EVAP DTCs must be repaired
before continuing.
Is the Good Trip Counter displayed and equal to zero?
Yes → Go To 2
No
2 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.
Install a fuel pressure gauge.
Ignition on, engine not running.
With the DRBIII , actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 379 KPa +/- 14 KPa (55 psi +/- 2 psi).
Choose a conclusion that best matches your fuel pressure reading.
Within Specification
Above Specification
Caution: Stop All Actuations.
3 Ignition on, engine not running.
With the DRBIII , read the O2 Sensor voltage.
Is the O2 Sensor voltage above 4.5 volts?
Yes → Go To 4
No
4 Turn the ignition off.
NOTE: Wait a minimum of 10 minutes to allow the O2 Sensor to cool down
before continuing the test. Allow the O2 Sensor voltage to stabilize between
4 and 5 volts.
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.
No
ACTION
→ Refer to the INTERMITTENT CONDITION Symptom (Diagnos-
tic Procedure).
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Go To 3
Replace the fuel filter/pressure regulator.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
→ Go To 11
Perform POWERTRAIN VERIFICATION TEST VER - 5.
→ Go To 5
DRIVEABILITY - GAS
Continued
77
APPLICABILITY
All
All
All
All