TEST
ACTION
APPLICABILITY
10
Turn the ignition on.
Disconnect the O2 Sensor harness connector.
With the DRBIII
t, monitor the O2 Sensor voltage.
Is the O2 Sensor voltage between 0.40 to 0.60 volts?
All
Yes
→ Replace the O2 Sensor
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 11
11
Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the O2 Sensor Signal circuit in the PCM harness connector
to ground.
Is the resistance below 5.0 ohms?
All
Yes
→ Repair the O2 Sensor Signal for a short to ground.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 12
12
NOTE: Before Continuing: Disconnect the PCM harness connector and
check the related wiring terminals for corrosion, damage or terminal push
out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay
particular attention to all Power and Ground circuits.
If there are no possible causes remaining, view repair.
All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
13
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.
Raise vehicle on hoist, and disconnect the fuel pressure line at the fuel pump module.
Install special 5/16 fuel line adapter tool #6539 between disconnected fuel line and
the fuel pump module.
Attach a fuel pressure test gauge to the T fitting on tool #6539.
Turn the ignition on.
With the DRBIII
t, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58 psi +/- 5 psi).
Is the fuel pressure within specification?
All
Yes
→ Repair or replace fuel supply line as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 14
Caution: Stop All Actuations.
80
DRIVEABILITY - SBEC
P0171-1/1 FUEL SYSTEM LEAN —
Continued