oxygen MITSUBISHI MONTERO 1998 User Guide
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1998, Model line: MONTERO, Model: MITSUBISHI MONTERO 1998Pages: 1501, PDF Size: 25.81 MB
Page 720 of 1501

TROUBLE CODE DEFINITION
When DTC is obtained, refer to appropriate DTC test
procedure.
DIAGNOSTIC TROUBLE CODES (DTCS)
NOTE: DTCs can only be retrieved by using a scan tool. Listed DTCs
are retrieved using a generic scan tool. MUT II scan tool
can be used, but it may not read all DTCs. DTCS listed are
not used on all vehicles.
DTC P0100
Volume Airflow (VAF) circuit failure. Possible causes are:
connector or harness, or faulty VAF sensor.
DTC P0105
Barometric (BARO) pressure circuit failure. Possible causes
are: connector or harness, or faulty BARO pressure sensor.
DTC P0105
Manifold Absolute Pressure (MAP) circuit failure. Possible
causes are: connector or harness, or faulty MAP sensor.
DTC P0110
Intake Air Temperature (IAT) circuit failure. Possible causes\
are: connector or harness, or faulty VAF sensor.
DTC P0115
Engine Coolant Temperature (ECT) circuit failure. Possible
causes are: connector or harness, or faulty ECT sensor.
DTC P0120
Throttle Position (TP) circuit failure. Possible causes are:
connector or harness, or faulty TP sensor.
DTC P0125
Excessive time to enter closed loop fuel control. Possible
causes are: faulty front HO2S, HO2S connector or harness, or faulty
fuel injector.
DTC P0130
Front Heated Oxygen Sensor (HO2S) circuit failure. Possible
causes are: connector or harness, or faulty HO2S.
DTC P0135
Front Heated Oxygen Sensor (HO2S) heater circuit failure.
Possible causes are: connector or harness, or faulty HO2S.
DTC P0136
Rear Heated Oxygen Sensor (HO2S) circuit failure. Possible
causes are: connector or harness, or faulty HO2S.
DTC P0141
Rear Heated Oxygen Sensor (HO2S) heater circuit failure.
Possible causes are: connector or harness, or faulty HO2S.
DTC P0150
Heated Oxygen Sensor (HO2S) circuit failure (bank 2, sensor
1). Possible causes are: connector or harness, or HO2S.
Page 721 of 1501

DTC P0155
Heated Oxygen Sensor (HO2S) heater circuit failure (bank 2,
sensor 1). Possible causes are: connector or harness, or HO2S.
DTC P0156
Heated Oxygen Sensor (HO2S) circuit failure (bank 2, sensor
2). Possible causes are: connector or harness, or HO2S.
DTC P0161
Heated Oxygen Sensor (HO2S) heater circuit failure (bank 2,
sensor 2). Possible causes are: connector or harness, or HO2S.
DTC P0170
Fuel trim failure (bank 1). Possible causes are: intake air
leaks, cracked exhaust manifold, faulty VAF sensor frequency, HO2S,
injector, fuel pressure, ECT, IAT or BARO pressure sensor.
DTC P0173
Fuel trim failure (bank 2). Possible causes are: intake air
leaks, cracked exhaust manifold, faulty VAF sensor frequency, HO2S,
injector, fuel pressure, ECT, IAT or BARO pressure sensor.
DTC P0201
Cylinder No. 1 injector circuit failure. Possible causes are:
connector or harness, or faulty injector.
DTC P0202
Cylinder No. 2 injector circuit failure. Possible causes are:
connector or harness, or faulty injector.
DTC P0203
Cylinder No. 3 injector circuit failure. Possible causes are:
connector or harness, or faulty injector.
DTC P0204
Cylinder No. 4 injector circuit failure. Possible causes are:
connector or harness, or faulty injector.
DTC P0205
Cylinder No. 5 injector circuit failure. Possible causes are:
connector or harness, or faulty injector.
DTC P0206
Cylinder No. 6 injector circuit failure. Possible causes are:
connector or harness, or faulty injector.
DTC P0300
Random misfire detected. Possible causes are: connector or
harness, faulty ignition coil, ignition power transistor, spark plug,
ignition circuit, injector, HO2S, compression pressure, timing belt,
air intake system, fuel pressure, or CKP sensor.
DTC P0301
Cylinder No. 1 misfire detected. Possible causes are:
connector or harness, faulty ignition coil, ignition power transistor,
spark plug, ignition circuit, injector, HO2S, compression pressure,
timing belt, air intake system, fuel pressure, or CKP sensor.
DTC P0302
Cylinder No. 2 misfire detected. Possible causes are:
connector or harness, faulty ignition coil, ignition power transistor,
spark plug, ignition circuit, injector, HO2S, compression pressure,
timing belt, air intake system, fuel pressure, or CKP sensor.
Page 750 of 1501

test vehicle (if necessary) and attempt to duplicate conditions that
caused original complaint. Recheck for DTCs. If no DTCs are displayed,
go to INTERMITTENT DTCS .
DTC P0125: EXCESSIVE TIME TO ENTER CLOSED LOOP FUEL CONTROL
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
Specific self-diagnostic test not available from manufacturer
at time of publication. Check front heated oxygen sensor, fuel
injectors, and related connectors and harnesses. Also, see F - BASIC
TESTING article.
DTC P0130, P0135, P0150 & P0155: FRONT HEATED OXYGEN SENSOR
(HO2S) CIRCUIT FAILURE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) If using scan tool, go to step 3). Disconnect front HO2S
connector. Install Test Harness (MB998464) between HO2S and HO2S
connector. Using DVOM, check resistance between specified HO2S
connector heater terminals. See
FRONT HO2S CONNECTOR TERMINAL IDENTIFICATION table. HO2S resistance
should be 11-18 ohms at 68
F (20C). If resistance is not as
specified, replace HO2S. If resistance is as specified, go to next
step.
2) Start and warm engine to operating temperature. Using
jumper wires, apply 12 volts and ground to specified HO2S connector
heater terminals. See FRONT HO2S CONNECTOR TERMINAL IDENTIFICATION
table. Using DVOM, check voltage between specified HO2S connector
output terminals, while repeatedly racing engine. If voltage is not .
6-1.0 volt, replace HO2S. If voltage is .6-1.0 volt, go to step 5).
FRONT HO2S CONNECTOR TERMINAL IDENTIFICATION TABLE
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Application (1) Heater Terminals No. Output Terminals No.
Montero & 3000GT ......... 1 & 3 ........................... 2 & 4
( 1) - First terminal listed is positive. Second terminal listed is
negative.
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3) Start and warm engine to operating temperature. Using scan
tool, read HO2S voltage. See HO2S ITEM LIST IDENTIFICATION table for
appropriate scan tool item number. While monitoring scan tool,
accelerate to 4000 RPM. Suddenly decelerate. Scan tool should read 0.2
volt or less. Suddenly accelerate. Scan tool should read 0.6-1.0 volt.
If voltage is not as specified, replace HO2S. If voltage is as
specified, go to next step.
HO2S ITEM LIST IDENTIFICATION TABLE
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Application Item No.
Montero - Federal
Front ......................................................... 11
Rear .......................................................... 59
Except Montero - Federal
Page 751 of 1501

Front
Left ........................................................ 39
Right ....................................................... 11
Rear
Left ........................................................ 69
Right ....................................................... 59
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4) While monitoring scan tool, accelerate to 2500 RPM and
decelerate to 700 RPM (idle). Scan tool should switch from 0.6-1.0
volt to 0.4 volt or less. If voltage is not as specified, replace
HO2S. If voltage is as specified, go to next step.
5) On 3000GT, go to next step. On Montero, disconnect HO2S
connector and MFI relay connector. Using DVOM, check for continuity
between HO2S connector terminal No. 1 and MFI relay connector terminal
No. 1. If continuity does not exist, repair wiring harness as
necessary. If continuity exists, go to step 7).
6) Disconnect HO2S connector. Turn ignition switch to ON
position. Using DVOM, check voltage between chassis ground and HO2S
connector terminal No. 1. If battery voltage does not exists, repair
wiring harness as necessary. If battery voltage exists, go to next
step.
7) Turn ignition switch to OFF position. With HO2S connector
disconnected, disconnect PCM connector. Using DVOM, check for open or
short circuit between specified HO2S connector terminal and PCM
connector terminal. See
FRONT HO2S-TO-PCM HARNESS TERMINAL IDENTIFICATION table. If open or
short circuit exists, repair wiring harness as necessary. If open or
short circuit does not exist, go to next step.
FRONT HO2S-TO-PCM HARNESS TERMINAL IDENTIFICATION TABLE
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Application HO2S Terminal No. PCM Terminal No.
Montero - Federal .......... 3 ....................... 3
4 ...................... 71
All Others .............. ( 1) 3 ...................... 3
( 2) 3 ...................... 4
( 1) 4 ..................... 71
( 2) 4 ..................... 72
( 1) - Left front HO2S.
( 2) - Right front HO2S.
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8) Using DVOM, check for continuity between chassis ground
and HO2S connector terminal No. 2. If continuity does not exist,
repair wiring harness as necessary. If continuity exists, go to next
step.
9) Condition required to set DTC is not present at this time.
Test is complete. Intermittent problem may exist. Road test vehicle
(if necessary) and attempt to duplicate conditions that caused
original complaint. Recheck for DTCs. If no DTCs are displayed, go to
INTERMITTENT DTCS .
DTC P0136, P0141, P0156 & P0161: REAR HEATED OXYGEN SENSOR
(HO2S) CIRCUIT FAILURE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) If using scan tool, go to next step. Disconnect rear HO2S
Page 753 of 1501

original complaint. Recheck for DTCs. If no DTCs are displayed, go to
INTERMITTENT DTCS.
DTC P0170 & P0173: FUEL TRIM FAILURE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) Specific self-diagnostic test not available from
manufacturer at time of publication. Check volume airflow sensor, fuel
injectors, engine coolant temperature sensor, intake air temperature
sensor, barometric or manifold absolute pressure sensor, heated oxygen
sensor. See appropriate DTC test. Check related connectors and
harnesses. See L - WIRING DIAGRAMS article.
2) Also check fuel pressure, check for intake air leaks, and
for cracked manifold. See F - BASIC TESTING article.
DTC P0201-P0206: FUEL INJECTOR CIRCUIT FAILURE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) If using scan tool, go to step 3). Using a stethoscope or
long-bladed screwdriver, listen for clicking sound from each fuel
injector while engine is running or being cranked. If no sound is
heard from fuel injector(s), check fuel injector connections. Repair
connections as necessary. If connections are okay, go to next step.
2) Ensure engine coolant temperature is at 68
F (20C).
Disconnect fuel injector connector. Using DVOM, check resistance
between specified fuel injector terminals. See
FUEL INJECTOR TERMINAL IDENTIFICATION table. If resistance is not 2.0-
3.0 3000GT turbo or 13-16 ohms on all other models, replace fuel
injector(s). If resistance is as specified, go to step 6).
FUEL INJECTOR TERMINAL IDENTIFICATION TABLE
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Application Terminals No.
Montero ( 1) ........................................ 8 & 1
8 & 2
8 & 3
8 & 5
8 & 6
8 & 7
3000GT - Rear Bank ( 2)
Non-Turbo ........................................ 1 & 2
1 & 5
1 & 6
Turbo ............................................ 1 & 4
2 & 8
4 & 5
4 & 6
4 & 7
4 & 8
( 1) - Check resistance at intermediate fuel injector
connector (component side).
( 2) - Check resistance at rear fuel injector connector
(component side).
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Page 756 of 1501

L - WIRING DIAGRAMS article.
1) Specific self-diagnostic test is not available from
manufacturer at time of publication. Check ignition coil, power
transistor, spark plugs, fuel injectors, heated oxygen sensor,
crankshaft position sensor, and related connectors and harnesses.
2) Also check compression pressure, timing belt, fuel
pressure, and for intake air leaks. See F - BASIC TESTING article.
DTC P0325: KNOCK SENSOR (KS) NO. 1 CIRCUIT FAILURE
NOTE: This test applies to 3000GT equipped with DOHC engine only.
For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
1) Component or scan tool testing procedure not available
from manufacturer at time of publication. Turn ignition switch to OFF
position. Disconnect KS connector and PCM connector. Ground PCM
connector terminal No. 91. Go to next step.
2) Using DVOM, check for continuity between chassis ground
and KS connector terminal No. 1. If continuity does not exist, repair
wiring harness as necessary. If continuity exists, go to next step.
3) Remove jumper wire from PCM connector terminal No. 1.
Check for continuity between chassis ground and KS connector terminal
No. 2. If continuity does not exist, repair wiring harness as
necessary. If continuity exists, go to next step.
4) Test is complete. Intermittent problem may exist. Road
test vehicle (if necessary) and attempt to duplicate conditions that
caused original complaint. Recheck for DTCs. If no DTCs are displayed,
go to INTERMITTENT DTCS .
DTC P0335: CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT FAILURE
NOTE: For terminal identification, see TERMINAL IDENTIFICATION. For
circuit and wire color identification, see
L - WIRING DIAGRAMS article.
NOTE: Procedures are provided by manufacturer for component
testing using an engine analyzer with oscilloscope
capability. Refer to manufacturer's operation manual for
instructions in use of oscilloscope.
1) If using scan tool, go to step 3). Disconnect CKP sensor
connector. Install Test Harness (MB991348) between CKP sensor and
connector. Using engine analyzer with oscilloscope capability, connect
special patterns probe to CKP sensor connector terminal No. 2. Go to
next step.
2) Start engine. Compare oscilloscope wave pattern with
known-good wave pattern. See Fig. 38. Verify wavelength (time)
decreases as engine RPM increases. If wave pattern fluctuates to left
or right, check for loose timing belt or an abnormality in sensor
pick-up disc. If a rectangular wave pattern is generated even when
engine is not started, substitute known-good CKP sensor. Repeat test.
If wave pattern is still abnormal, go to step 6).
Fig. 38: Identifying Known-Good CKP Sensor Wave Pattern
Courtesy of Mitsubishi Motor Sales of America
Page 796 of 1501

* Check power supply to PCM.
* Check fuel pressure.
* Check ignition timing.
* Check for disconnected or damaged vacuum hoses.
* Check for control relay malfunction.
* Check for SFI system malfunction.
* Check for fuel pump drive control system malfunction.
* Check for ignition coil malfunction.
* Check for power transistor malfunction (if applicable).
* Check for fuel injector malfunction.
* Check for PCM malfunction.
* Ensure electrical harness, connectors and wires are not
broken, bent or loose.
ROUGH OR UNSTABLE IDLE
* Check intake air temperature sensor.
* Check EVAP purge control solenoid valve (if applicable).
* Check vehicle speed sensor.
* Check engine coolant temperature sensor.
* Check barometric pressure sensor (if applicable).
* Check manifold absolute pressure sensor (if applicable).
* Check ignition switch.
* Check throttle position sensor.
* Check camshaft position sensor.
* Check crankshaft position sensor.
* Check power steering oil pressure switch (if applicable).
* Check A/C switch and power relay (if applicable).
* Check park/neutral position switch (A/T).
* Check heated oxygen sensor.
* Check volume airflow sensor.
* Check fuel pressure.
* Check for disconnected or damaged vacuum hoses.
* Check for SFI system malfunction.
* Check idle air control (DC) motor (if applicable).
* Check idle air control (stepper) motor (if applicable).
* Check for fuel injector malfunction.
* Check for power transistor malfunction (if applicable).
* Check for vehicle speed sensor malfunction.
* Check for PCM malfunction.
* Ensure electrical harness, connectors and wires are not
broken, bent or loose.
ENGINE HESITATES OR POOR ACCELERATION
* Check intake air temperature sensor.
* Check engine coolant temperature sensor.
* Check barometric pressure sensor (if applicable).
* Check manifold absolute pressure sensor (if applicable).
* Check ignition switch.
* Check ignition coil.
* Check EGR control solenoid valve (if applicable).
* Check throttle position sensor.
* Check camshaft position sensor.
* Check crankshaft position sensor.
* Check power steering oil pressure switch (if applicable).
* Check A/C switch and power relay (if applicable).
* Check park/neutral position switch (A/T).
* Check heated oxygen sensor.
* Check volume airflow sensor.
* Check fuel pressure.
* Check for disconnected or damaged vacuum hoses.
* Check for SFI system malfunction.
Page 797 of 1501

* Check idle air control (DC) motor (if applicable).
* Check idle air control (stepper) motor (if applicable).
* Check for fuel injector malfunction.
* Check for power transistor malfunction (if applicable).
* Check A/C switch and power relay (if applicable).
* Check for PCM malfunction.
* Ensure electrical harness, connectors and wires are not
broken, bent or loose.
ENGINE SURGES
* Check engine coolant temperature sensor.
* Check EGR control solenoid valve (if applicable).
* Check fuel pressure.
* Check for fuel injector malfunction.
DETONATION OR KNOCKING
* Check for knock sensor malfunction (if applicable).
* Check volume airflow sensor.
* Check for engine cooling system problems.
* Check fuel quality.
* Check intake air temperature sensor.
* Check barometric pressure sensor (if applicable).
* Check manifold absolute pressure sensor (if applicable).
* Check ignition coil.
* Check power transistor (if applicable).
* Check for EGR system malfunction.
POOR FUEL MILEAGE
* Check intake air temperature sensor.
* Check engine coolant temperature sensor.
* Check barometric pressure sensor (if applicable).
* Check manifold absolute pressure sensor (if applicable).
* Check ignition switch.
* Check throttle position sensor.
* Check camshaft position sensor.
* Check crankshaft position sensor.
* Check power steering oil pressure switch (if applicable).
* Check A/C switch and power relay (if applicable).
* Check park/neutral position switch (A/T).
* Check heated oxygen sensor.
* Check volume airflow sensor.
* Check fuel pressure.
* Check for SFI system malfunction.
* Check idle air control (DC) motor (if applicable).
* Check idle air control (stepper) motor (if applicable).
* Check for fuel injector malfunction.
* Check for power transistor malfunction (if applicable).
INTERMITTENTS
INTERMITTENT PROBLEM DIAGNOSIS
Intermittent fault testing requires duplicating circuit or
component failure to identify problem. These procedures may lead to
computer setting a Diagnostic Trouble Code (DTC) which may help in
diagnosis.
If problem vehicle does not produce DTCs, monitor voltage or
resistance values using a DVOM while attempting to reproduce
conditions causing intermittent fault. A status change on DVOM
Page 814 of 1501

Starters
Generator .................................. Generators & Regulators
Engine Performance
Power Distribution
Generic Electronic Module (GEM) ............... Body Control Modules\
Electronic Suspension
Glow Plug Relay ................................. Engine Performance
Glow Plugs ...................................... Engine Performance
Grounds ........................................ Ground Distribution
Headlight Door Module .............................. Headlight Doors
Headlight Relay .................................. Headlight Systems
Daytime Running Lights
Headlights ....................................... Headlight Systems
Daytime Running Lights
Heated Oxygen Sensor(s) (HO2S) .................. Engine Performan\
ce
Heated Windshield Control Module ................ Heated Windshields
Height Sensor ................................ Electronic Suspension
Horns ..................................... Steering Column Switches
Horn Relay ................................ Steering Column Switches
Idle Air Control (IAC) Motor/Valve .............. Engine Performance\
Ignition Coil(s) ................................ Engine Performance\
Ignition Key Lock Cylinder ....................... Anti-Theft System
Ignition Module ................................. Engine Performance
Ignition Switch ................................. Power Distribution
Engine Performance
Generators & Regulators
Starters
Illuminated Entry Module .............. Illumination/Interior Lights
Illumination Lights ................... Illumination/Interior Lights
Impact Sensor ............................. Air Bag Restraint System
Inertia Fuel Shutoff Switch ..................... Engine Performance
Inhibit Relay ............................................. Starters
Instrument Cluster ........................ Analog Instrument Panels
Intake Air Temperature (IAT) Sensor ............. Engine Performance\
Interior Lights ....................... Illumination/Interior Lights
Interlock Switch .......................................... Starters
Junction Block .................................. Power Distribution
Keyless Entry Receiver ........................ Remote Keyless Entry
Key Reminder Switch ....................................... Starters
Knock Sensor .................................... Engine Performance
Lamp Control Module ................................ Exterior Lights
License Plate Lamp ................................. Exterior Lights
Lighting Control Module ................... Lighting Control Modules
Anti-Theft System
Daytime Running Lights
Headlight Systems
Lower Relay .................................. Power Convertible Top
Malfunction Indicator Light (MIL) ............... Engine Performance\
Instrument Panels
Manifold Absolute Pressure (MAP) Sensor ......... Engine Performance\
Mass Airflow (MAF) Sensor ....................... Engine Performance\
Mega Fuse .................................. Generators & Regulators
Memory Seat/Mirror Module ........................... Memory Systems
Mirror Defogger ............................... Rear Window Defogger
Moon Roof Motor .................................... Power Moon Roof
Moon Roof Relay .................................... Power Moon Roof
Multi-Function Control Module ...................... Warning Systems
Neutral Safety Switch ..................................... Starters
Oil Level Switch ................................ Engine Performance
Oil Pressure Switch/Sending Unit .......... Analog Instrument Panels
Engine Performance
Overhead Console .................................. Overhead Console
Oxygen Sensor(s) (O2S) .......................... Engine Performan\
ce
Page 820 of 1501

THROTTLE POSITION (TP) SWITCH or THROTTLE POSITION (TP) SENSOR in G \
-
TESTS W/CODES article.
Engine Coolant Temperature Sensor
See G - TESTS W/CODES article.
Heated Oxygen Sensor
See G - TESTS W/CODES article.
Intake Air Temperature (IAT) Sensor
On all models except Eclipse 2.0L non-turbo and Mirage 1.5L,
IAT sensor is a part of volume airflow sensor assembly. On all models,
see G - TESTS W/CODES article.
Manifold Absolute Pressure Sensor
See G - TESTS W/CODES article.
Manifold Differential Pressure Sensor
See G - TESTS W/CODES article.
Power Steering Oil Pressure (PSP) Switch
On Eclipse 2.0L non-turbo, see DTC 115 in G - TESTS W/CODES -
NON-TURBO article. On all other models except Eclipse 2.0L non-turbo,
see G - TESTS W/CODES article.
Throttle Position Sensor
See G - TESTS W/CODES article.
Vehicle Speed Sensor
See G - TESTS W/CODES article.
Volume Airflow Sensor
See G - TESTS W/CODES article.
MOTORS, RELAYS & SOLENOIDS
MOTORS
Idle Air Control Motor
See G - TESTS W/CODES article.
RELAYS
ASD, Fuel Pump & MFI Relay
See G - TESTS W/CODES article.
Radiator Cooling Fan Control Relay (High & Low)
See G - TESTS W/CODES article.
SOLENOIDS
EGR Control Solenoid Valve
See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS &
SUB-SYSTEMS.
EVAP Purge Control Solenoid Valve
See FUEL EVAPORATION under EMISSION SYSTEMS & SUB-SYSTEMS.
Fuel Pressure Regulator Control Solenoid Valve (Turbo Models)
See FUEL DELIVERY under FUEL SYSTEM.
Wastegate Control Solenoid Valve