Isuzu 1999 RODEO Workshop Manual page 1004

RESTRICTED EXHAUST SYSTEM CHECK
Step
1 Was the On–Board Diagnostic (OBD) System Check
performed?
2 1. Remove the HO2S2.
f
For removal procedures, refer to Heated
Oxygen Sensors in On–Vehicle Service.
2. Install the Exhaust Backpressure Tester in place of
the Bank 1 HO2S.
3. Idle the engine at normal operating temperature.
Does the reading on the gauge exceed the specified
value?
3 With the exhaust back–pressure tester in place of
HO2S, and
temperature:
Increase the engine speed to 2000 RPM while
observing the gauge.
Does the reading exceed the amount of the value
column?
4 1. Re–install the HO2S2. (Refer to Heated Oxygen
Sensors in On–Vehicle Service for installation
procedure.)
2. Remove the HO2S1.
3. Install the Exhaust Back–Pressure Tester BT8515V
or equivalent in place of the HO2S1.
4. Bring the engine to normal operating temperature
while observing the gauge.
5. Increase the engine speed to 2000 RPM (allow 10
seconds for pressure build) and observe the gauge.
Did the reading exceed the specified value?
5 Repair a restiction in the exhaust system after the
catalytic converter.
Possible faults include:
f
Collapsed pipe
f
Internal muffler failure
6 Replace the restricted catalytic converter.
NOTE: Diagnostic Trouble Codes 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 Diagnostic
Trouble Codes that were set by the lack of O2 sensor
activity.
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
Action
the engine at normal
Value(s)
—
8.62 kPa
(1.25 psi)
operating
8.62 kPa
(1.25 psi)
8.62 kPa
(1.25 psi)
—
—
6E1–377
Yes No
Go to OBD
System
Go to Step 2 Check
Go to Step 5 Go to Step 3
Go to Step 5 Go to Step 4
Go to Step 6 System OK
Verify repair —
Verify repair —