TEST
ACTION
APPLICABILITY
9
Turn the ignition on.
With the DRBIII
t, read TPS voltage.
NOTE: The throttle must be against the stop.
Is the voltage 0.92 or less with the Throttle closed?
All
Yes
→
Go To
10
No
→
Check for a binding throttle condition. If OK, replace the Throttle
Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
10
Turn the ignition on.
With the DRBIII
t, read the TPS voltage.
While monitoring the DRBIII
t, slowly open and close the throttle.
Does the voltage increase and decrease smoothly?
All
Yes
→
Go To
11
No
→
Replace the Throttle Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
11
Turn the ignition off.
Connect a Vacuum Gauge to a Manifold Vacuum source.
Start the engine.
Allow the engine to idle.
Note: If engine will not idle, maintain a constant RPM above idle.
With the DRBIII
t in Sensors, read the MAP Sensor vacuum value.
Is the DRB reading within 1
9 of the Vacuum Gauge reading?
All
Yes
→
Go To
12
No
→
Replace the MAP Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
12
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)
Turn the ignition on.
With the DRBIII
t, 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
All
Yes
→
Go To
13
No
→
Replace the Engine Coolant Temperature Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
121
DRIVEABILITY - GAS
P0172-1/1 FUEL SYSTEM RICH —
Continued