Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 1238

6E1–28

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

Engine Component Locator Table

Number

Name

Location

1

Engine Coolant Temperature (ECT) Sensor

Rear of engine, near ignition coils

2

Linear Exhaust Gas Recirculation (EGR) Valve

On the left rear of the engine at the bulkhead

3

Heated Oxygen Sensor (HO2S), Bank 1,
Sensor 1

On the exhaust pipe, left side of engine,
immediately behind the exhaust manifold

4

Air Cleaner

Left front of the engine bay

5

Intake Air Temperature (IAT) Sensor

On the intake air duct near the air cleaner

6

Camshaft Position (CMP) Sensor

Inside the front cover assembly

7

Positive Crankcase Ventilation (PCV) Port

On the right front corner of the valve cover

8

Fuel Pressure Regulator

On the forward end of the fuel rail, to the right of
the PVC port

9

Throttle Body

Between the intake air duct and the intake
manifold

10

Fuse/Relay Box

Along the inside of the right fender

11

Throttle Position (TP) Sensor

On the front of the throttle body

12

Idle Air Control (IAC) Valve

On the rear of the throttle body

13

EVAP Canister Vent Solenoid

At the right rear of the engine, behind the Throttle
body

14

Ignition Control Module (ICM)

Mounted on a heat sink on the lower right side of
the engine block, above the starter motor

15

Manifold Absolute Pressure (MAP) Sensor

Bolted to the front edge of the intake manifold,
under the fuel rail

16

Knock Sensor

Left side engine block.

Undercarriage Component Locator Table

Name

Location

Fuel Pump Assembly

Installed in the top of the fuel tank

EVAP Canister

Behind rear axle, near fuel tank filler nozzle

EVAP Canister Purge Valve Solenoid

Behind rear axle, near fuel tank filler nozzle

Heated Oxygen Sensor (HO2S) Bank 1,
Sensor 2

Threaded into the exhaust pipe behind the catalytic converter

Vehicle Speed Sensor (VSS)

Protrudes from the right side of the transmission housing, near the
output shaft

Crankshaft Position (CKP) Sensor

Lower left hand front of engine, behind power steering pump bracket

6E1–29

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

Fuse And Relay Panel (Underhood Electrical Center)

Underhood (U/H) Fuse and Relay Panel

060R100016

6E1–30

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

DIAGNOSIS Strategy–Based

Diagnostics

Strategy–Based Diagnostics

The strategy–based diagnostic is a uniform approach to
repair all Electrical/Electronic (E/E) systems. The
diagnostic flow can always be used to resolve an E/E
system problem and is a starting point when repairs are
necessary. The following steps will instruct the technician
how to proceed with a diagnosis:

1. Verify the customer complaint.

D

To verify the customer complaint, the technician
should know the normal operation of the system.

2. Perform preliminary checks.

D

Conduct a thorough visual inspection.

D

Review the service history.

D

Detect unusual sounds or odors.

D

Gather diagnostic trouble code information to
achieve an effective repair.

3. Check bulletins and other service information.

D

This includes videos, newsletters, etc.

4. Refer to service information (manual) system

check(s).

D

”System checks” contain information on a system
that may not be supported by one or more DTCs.
System checks verify proper operation of the
system. This will lead the technician in an
organized approach to diagnostics.

5. Refer to service diagnostics.

DTC Stored

Follow the designated DTC chart exactly to make an
effective repair.

No DTC

Select the symptom from the symptom tables. Follow the
diagnostic paths or suggestions to complete the repair.
You may refer to the applicable component/system check
in the system checks.

No Matching Symptom

1. Analyze the complaint.
2. Develop a plan for diagnostics.
3. Utilize the wiring diagrams and the theory of

operation.

Combine technician knowledge with efficient use of the
available service information.

Intermittents

Conditions that are not always present are called
intermittents. To resolve intermittents, perform the
following steps:

1. Observe history DTCs, DTC modes, and

freeze–frame data.

2. Evaluate the symptoms and the conditions described

by the customer.

3. Use a check sheet or other method to identify the

circuit or electrical system component.

4. Follow the suggestions for intermittent diagnosis

found in the service documentation.

Most Scan Tools, such as the Tech 2, have
data–capturing capabilities that can assist in detecting
intermittents.

No Trouble Found

This condition exists when the vehicle is found to operate
normally. The condition described by the customer may
be normal. Verify the customer complaint against another
vehicle that is operating normally. The condition may be
intermittent. Verify the complaint under the conditions
described by the customer before releasing the vehicle.

1. Re–examine the complaint.

When the complaint cannot be successfully found or
isolated, a re–evaluation is necessary. The complaint
should be re–verified and could be intermittent as
defined in 

 Intermittents, or could be normal.

2. Repair and verify.

After isolating the cause, the repairs should be made.
Validate for proper operation and verify that the
symptom has been corrected. This may involve road
testing or other methods to verify that the complaint
has been resolved under the following conditions:

D

Conditions noted by the customer.

D

If a DTC was diagnosed, verify a repair by
duplicating conditions present when the DTC was
set as noted in the Failure Records or Freeze
Frame data.

Verifying Vehicle Repair

Verification of the vehicle repair will be more
comprehensive for vehicles with OBD II system
diagnostics. Following a repair, the technician should
perform the following steps:

IMPORTANT:

Follow the steps below when you verify

repairs on OBD II systems. Failure to follow these steps
could result in unnecessary repairs.

1. Review and record the Failure Records and the

Freeze Frame data for the DTC which has been
diagnosed (Freeze Fame data will only be stored for
an A or B type diagnostic and only if the MIL (”Check
Engine” lamp) has been requested).

2. Clear the DTC(s).
3. Operate the vehicle within conditions noted in the

Failure Records and Freeze Frame data.

4. Monitor the DTC status information for the DTC which

has been diagnosed until the diagnostic test
associated with that DTC runs.

6E1–31

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

GENERAL SERVICE 

INFORMATION

OBD II Serviceability Issues

With the introduction of OBD II diagnostics across the
entire passenger car and light–duty truck market in 1996,
illumination of the MIL (”Check Engine” lamp) due to a
non–vehicle fault could lead to misdiagnosis of the
vehicle, increased warranty expense and customer
dissatisfaction. The following list of non–vehicle faults
does not include every possible fault and may not apply
equally to all product lines.

Fuel Quality
Fuel quality is not a new issue for the automotive industry,
but its potential for turning on the MIL (”Check Engine”
lamp) with OBD II systems is new.
Fuel additives such as ”dry gas” and ”octane enhancers”
may affect the performance of the fuel. If this results in an
incomplete combustion or a partial burn, it will show up as
a Misfire DTC P0300. The Reid Vapor Pressure of the fuel
can also create problems in the fuel system, especially
during the spring and fall months when severe ambient
temperature swings occur. A high Reid Vapor Pressure
could show up as a Fuel Trim DTC due to excessive
canister loading. High vapor pressures generated in the
fuel tank can also affect the Evaporative Emission
diagnostic as well.
Using fuel with the wrong octane rating for vehicle may
cause driveability problems. Many of the major fuel
companies advertise that using ”premium” gasoline will
improve the performance of vehicle. Most premium fuels
use alcohol to increase the octane rating of the fuel.
Although alcohol–enhanced fuels may raise the octane
rating, the fuel’s ability to turn into vapor in cold
temperatures deteriorates. This may affect the starting
ability and cold driveability of the engine.
Low fuel levels can lead to fuel starvation, lean engine
operation, and eventually engine misfire.

Non–OEM Parts
All of the OBD II diagnostics have been calibrated to run
with OEM parts. Something as simple as a
high–performance exhaust system that affects exhaust
system back pressure could potentially interfere with the
operation of the EGR valve and thereby turn on the MIL
(”Check Engine” lamp). Small leaks in the exhaust
system near the post catalyst oxygen sensor can also
cause the MIL (”Check Engine” lamp) to turn on.
Aftermarket electronics, such as transceiver, stereos,
and anti–theft devices, may radiate EMI into the control
system if they are improperly installed. This may cause a
false sensor reading and turn on the MIL (”Check Engine”
lamp).

Environment
Temporary environmental conditions, such as localized
flooding, will have an effect on the vehicle ignition system.
If the ignition system is rain–soaked, it can temporarily
cause engine misfire and turn on the MIL (”Check Engine”
lamp).

Refueling
A new OBD II diagnostic was introduced in 1996 on some
vehicles. This diagnostic checks the integrity of the entire
evaporative emission system. If the vehicle is restarted
after refueling and the fuel cap is not secured correctly,
the on–board diagnostic system will sense this as a
system faultand turn on the MIL (”Check Engine” lamp)
with a DTC P0440.

Vehicle Marshaling
The transportation of new vehicles from the assembly
plant to the dealership can involve as many as 60 key
cycles within 2 to 3 miles of driving. This type of operation
contributes to the fuel fouling of the spark plugs and will
turn on the MIL (”Check Engine” lamp) with a P0300
Misfire DTC.

Poor Vehicle Maintenance
The sensitivity of OBD II diagnostics will cause the MIL
(”Check Engine” lamp) to turn ON if the vehicle is not
maintained properly. Restricted air filters, fuel filters, and
crankcase deposits due to lack of oil changes or improper
oil viscosity can trigger actual vehicle faults that were not
previously monitored prior to OBD II. Poor vehicle
maintenance can’t be classified as a ”non–vehicle fault”,
but with the sensitivity of OBD II diagnostics, vehicle
maintenance schedules must be more closely followed.

Severe Vibration
The Misfire diagnostic measures small changes in the
rotational speed of the crankshaft. Severe driveline
vibrations in the vehicle, such as caused by an excessive
amount of mud on the wheels, can have the same effect
on crankshaft speed as misfire and therefore may set a
Misfire DTC P0300.

Related System Faults
Many of the OBD II system diagnostics will not run if the
PCM detects a fault on a related system or component.
One example would be that if the PCM detected a Misfire
fault, the diagnostics on the catalytic converter would be
suspended until the Misfire fault was repaired. If the
Misfire fault was severe enough, the catalytic converter
could be damaged due to overheating and would never
set a Catalyst DTC until the Misfire fault was repaired and
the Catalyst diagnostic was allowed to run to completion.
If this happens, the customer may have to make two trips
to the dealership in order to repair the vehicle.

Emissions Control Information Label

The engine compartment ”Vehicle Emissions Control
Information Label” contains important emission
specifications and setting procedures. In the upper left
corner is exhaust emission information. This identifies the
emission standard (Federal, California, or Canada) of the
engine, the displacement of the engine in liters, the class
of the vehicle, and the type of fuel metering system. There
is also an illustrated emission components and vacuum
hose schematic.
This label is located in the engine compartment of every
vehicle. If the label has been removed it should be
replaced, it can be ordered from Isuzu Dealer ship.