Isuzu 2000 Trooper Workshop Manual page 1391

6E–522
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step
1 Was the "On-Board Diagnostic (OBD) System Check"
performed?
2 1. Remove the Bank 2 HO2S 2.
2. Install the
(BT-8515-V or equivalent) in place of the Bank 2
HO2S 2.
3. Run the engine at normal operating temperature.
4. Increase the engine speed to 2000 RPM and allow
10 seconds for pressure to build.
5. Observe the exhaust system backpressure reading
on the gauge.
Does the reading exceed the amount in the value
column?
3 Repair the restriction in the exhaust system after the
catalytic converter.
Possible faults include:
D
Collapsed pipe
D
Heat distress
D
Internal muffler failure
Is the action complete?
4 1. Install the Bank 2 HO2S 2.
2. Install the Exhaust Back pressure Tester in place of
Bank 1 HO2S 1.
3. Run the engine at normal operating temperature.
4. Increase the engine speed to 2000 RPM and allow
10 seconds for pressure to build.
5. Observe the exhaust system backpressure reading
on the gauge.
Does the reading exceed the amount in the value
column?
5 Repair the restriction in the catalytic converter.
Is the action complete?
NOTE: DTCs will be set by running the vehicle to normal
operating temperature after a cold start with the O2
sensor disconnected. After performing these tests, use
the Tech 2 to erase the DTCs that were set by the lack of
O2 sensor activity.
Bank 2 Restricted Exhaust System Check
Action
Exhaust Backpressure
Value(s)
—
Tester
8.62 kPa
(1.25 psi)
—
8.62 kPa
(1.25 psi)
—
Yes No
Go to OBD
System
Check
Go to Step 2
Go to Step 3 Go to Step 4
Verify repair —
No trouble
found. If a
driveability
symptom
exists, refer
to symptom
Go to Step 5
charts
Verify repair —