6E1–184
RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
DIAGNOSTIC TROUBLE CODE (DTC) P0172 SYSTEM TOO RICH (BANK 1)
060R100032
Circuit Description
To provide the best possible combination of driveability,
fuel economy, and emission control, a ”Closed Loop”
air/fuel metering system is used. While in ”Closed Loop”,
the powertrain control module (PCM) monitors the Bank 1
heated oxygen sensor (HO2S) 1 and adjusts fuel delivery
based upon the HO2S signal voltages. A change made to
fuel delivery will be indicated by the long and short term
fuel trim values which can be monitored with a Tech 2.
Ideal fuel trim values are around 0%; if the HO2S signals
are indicating a lean condition the PCM will add fuel,
resulting in fuel trim values above 0%. If a rich condition is
detected, the fuel trim values will be below 0%, indicating
that the PCM is reducing the amount of fuel delivered. If
an excessively rich condition is detected on Bank 1, the
PCM will set Diagnostic Trouble Code P0172. DTC
P0172 is a type B code.
The PCM’s maximum authority to control long term fuel
trim allows a range between –14% and +20%. The PCM’s
maximum authority to control short term fuel trim allows a
range between –11% and +20%. The PCM monitors fuel
trim under various engine speed/load fuel trim cells
before determining the status of the fuel trim diagnostic.
Conditions for Setting the DTC
D
No Tech 2 test is being run.
D
Engine run time more than 500 sec.
D
None of the following was set: EGR Diagnostic Trouble
Codes, HO2S Diagnostic Trouble Codes, (response,
transition, open, low volts, no activity), TPS Diagnostic
Trouble Codes, MAP Diagnostic Trouble Codes, IAT
Diagnostic Trouble Codes, canister purge Diagnostic
Trouble Codes, EVAP Diagnostic Trouble Codes,
injector circuit Diagnostic Trouble Codes, CKP
Diagnostic Trouble Code, ECT Diagnostic Trouble
Code, VSS Diagnostic Trouble Code, Idle Diagnostic
Trouble Code or misfire Diagnostic Trouble Codes.
D
Engine coolant temperature is between 65
°
C (149
°
F)
and 104
°
C (219
°
F).
D
Intake air temperature is between –40
°
C (–40
°
F) and
120
°
C(248
°
F).
D
Manifold absolute pressure is between 23.75 kPa and
99 kPa.
D
System voltage is greater than 9.5 volts.
D
Engine speed is between 400 and 6000 RPM.
D
Barometric pressure is greater than 72.3 kPa.
D
Engine is operating in ”Closed Loop”.
D
The average of the short term full trim samples is less
than 0.988 and the average of the adaptive index
multiplier samples is less 0.914.
Rich counter is more than 10 during 2.5 sec.