Chrysler 300M 2002 Service Manual page 2542

P0172-FUEL SYSTEM 1/1 RICH —
TEST
9 Note: For this test to be valid, the thermostat must be operating correctly.
Note: This test works best if performed on a cold engine (cold soak)
Ignition on, engine not running.
With the DRBIII , read the Engine Coolant Temperature Sensor value. If the engine
was allowed to sit overnight (cold soak), the temperature value should be a sensible
value that is somewhere close to the ambient temperature.
Note: If engine coolant temperature is above 82°C (180°F), allow the engine
to cool until 65°C (150°F) is reached.
Start the Engine.
During engine warm-up, monitor the Engine Coolant Temperature value. The temp
value change should be a smooth transition from start up to normal operating temp
82°C (180°F). The value should reach at least 82°C (180°F).
Did the Engine Coolant Temperature value increase a smooth transition and did it
reach at least 82°C
Yes → Go To 10
→ Replace the Engine Coolant Temperature Sensor.
No
10 Check for any of the following conditions/mechanical problems.
AIR INDUCTION SYSTEM - must be free from restrictions.
ENGINE VACUUM - must be at least 13 inches in neutral
ENGINE VALVE TIMING - must be within specifications
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks.
ENGINE PCV SYSTEM - must flow freely
TORQUE CONVERTER STALL SPEED - must be within specifications
POWER BRAKE BOOSTER - no internal vacuum leaks
FUEL - must be free of contamination
FUEL INJECTOR - plugged or restricted injector; control wire not connected to
correct injector
Are there any engine mechanical problems?
Yes → Repair as necessary.
→ Test Complete.
No
11 Ignition on, engine not running.
Disconnect the O2 Sensor harness connector.
With the DRBIII , monitor the O2 Sensor voltage.
O2 Sensor voltage should read 5.0 volts on the DRBIII
disconnected.
Using a jumper wire, jump from the O2 Sensor Signal circuit to the O2 Sensor Return
circuit in the O2 Sensor harness connector.
NOTE: The voltage should drop from 5.0 volts down to 2.5 volts with the
jumper wire connected.
Did the O2 Sensor voltage drop from 5 volts to 2.5 volts?
Yes → Replace the O2 Sensor
→ Go To 12
No
Continued
ACTION
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
DRIVEABILITY - NGC
with the connector
113
APPLICABILITY
All
All
All