engine oil MAZDA 6 2002 Suplement Service Manual

CONTROL SYSTEM
F1–33
F1
PCM INSPECTION (4WD)A6E394018880207Using SST (WDS or equivalent)
Note
•PIDs for the following parts are not available on this model. Go to the appropriate part inspection page.
—CMP sensor
—Main relay
1. Connect the SST (WDS or equivalent) to the
DLC-2.
2. Turn the ignition switch to ON position.
3. Measure the PID value.
•If PID value is not within the specification,
follow the instructions in Action column.
Note
•The PID/DATA MONITOR function monitors
the calculated value of the input/output
signals in the PCM. Therefore, an output
device malfunction is not directly indicated
as a malfunction of the monitored value for
the output device. If a monitored value of an
output device is out of specification, inspect the monitored value of the input device related to the output
control.
•For input/output signals except those of the monitoring items, use a voltmeter to measure the PCM
terminal voltage.
•The simulation items that are used in the ENGINE CONTROL SYSTEM OPERATION INSPECTION are
as follows.
—ACCS, ALTF, EVAPCP, FAN1, FAN2, FAN3, FP, HTR11, HTR12, IAC, IASV, IMRC, IMTV, VT DUTY1
PID/DATA monitor table (reference)
CONTROL SYSTEM
DLC-2
A6E3970W002
Monitor item
(Definition)Unit/
ConditionCondition/Specification
(Reference)ActionPCM
terminal
ACCS (A/C relay) ON/OFFIgnition switch ON: OFF
A/C switch ON and fan switch ON at
idle: ONInspect following PIDs: RPM, TP,
ECT, ACSW, TR.
Inspect A/C relay.4O
ACSW (A/C switch) ON/OFFA/C switch and fan switch ON at
ignition switch ON: OFF
A/C switch OFF at ignition switch
ON: OFFInspect A/C switch. 1AC
ALTF (Generator field
coil control duty value)%Ignition switch ON: 0%
Idle: 0—100%
Just after A/C switch ON and fan
switch ON at idle: Duty value risesInspect following PIDs: IAT, ECT,
RPM, VPWR, ALTT V.
Inspect generator.1AD
ALTT V (Generator
output voltage)VIgnition switch ON: 0 V
Idle: Approx. 14.9 V
*1 (E/L not
operating)Inspect generator. 1AA
ARPMDES
(Target engine speed)RPM
LF Unleaded fuel (RON 90 or
above) model
No load: 650 rpm
E/L operating: 700 rpm
P/S operating: 700 rpm
A/C ON: 750 rpm
L3 4WD ATX model
No load: 700 rpm
E/L operating: 700 rpm
P/S operating: 700 rpm
A/C ON: 700 rpm*
2, 750 rpm*3
Inspect following PIDs: IAT, RPM,
MAP, ECT, MAF, TP, INGEAR,
ACSW, TR, PSP, ALTT V.
Inspect IAC valve.
Inspect CKP sensor.—
AST (After start timer) Sec———

CONTROL SYSTEM
F1–37
F1
Without Using the SST
Caution
•The PCM terminal voltages vary with change in measuring conditions and vehicle conditions.
Always carry out a total inspection of the input systems, output systems, and PCM to determine
the cause of trouble. Otherwise, a wrong diagnosis will be made.
1. Measure the voltage at each terminal.
•If any incorrect voltage is detected, inspect the related system(s), wiring harnesses and connector(s)
referring to the Action column in the terminal voltage table.
Terminal voltage table (Reference)
Terminal Signal Connected to Test conditionVoltage
(V)Action
1A IGT1Ignition coil (No. 1,
4 cylinders)•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect ignition coil
•Inspect related
harness
1B IGT2Ignition coil (No. 2,
3 cylinders)•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect ignition coil
•Inspect related
harness
1C GND GND Under any condition Below 1.0•Inspect related
harness
1D GND GND Under any condition Below 1.0•Inspect related
harness
1E—— — ——
1F—— — ——
1G BARO BARO sensor Ignition switch ON (at sea level)Approx.
4.1 V•Inspect BARO sensor
•Inspect related
harness
1H—— — ——
1I—— — ——
1JManifold absolute
pressureMAP sensorIgnition switch ON (Engine OFF)Approx.
4.1•Inspect MAP sensor
•Inspect related
harness
IdleApprox.
1.5
1K Brake Brake switchBrake pedal depressed B+•Inspect brake switch
•Inspect related
harness Brake pedal released Below 1.0
1L—— — ——
1M ECT ECT sensorIgnition switch
ONECT 20 °C
{68 °F}3.04—
3.14•Inspect ECT sensor
•Inspect related
harness ECT 60 °C
{140 °F}1.29—
1.39
1N—— — ——
1O—— — ——
1P MAF MAF sensorIgnition switch ONApprox.
0.7•Inspect MAF sensor
•Inspect related
harness
Idle (after warm up)Approx.
1.3
1B 1A
1E 1D
1C 1H 1G 1J
1F 1I 1M
1L 1N 1K 1T 1Q1P 1S
1O 1R 1W1V
1Z 1Y
1X1AC1AB
1AA 1AD1U 2B 2A
2E 2D
2C 2H 2G 2J
2F 2I 2M
2L 2N 2K 2T 2Q2P 2S
2O 2R 2W2V
2Z 2Y
2X2AC2AB
2AA 2AD2U 3B 3A
3E 3D
3C 3H 3G 3J
3F 3I 3M
3L 3N 3K 3T 3Q3P 3S
3O 3R 3W3V
3Z 3Y
3X3AA3U 4B 4A
4E 4D
4C 4H 4G 4J
4F 4I 4M
4L 4N 4K 4T 4Q4P 4S
4O 4R 4W4V
4Z 4Y
4X4AC4AB
4AA 4AD4U
A6A3940W002

F1–42
CONTROL SYSTEM
4B Cooling fan control Cooling fan relay IdlingECT below 100
°C {212 °F}B+•Inspect cooling fan
relay
•Inspect related
harness A/C operating Below 1.0
4CVAD control*
5VAD control
solenoid valveIgnition switch
ONEngine speed
below 5,800
rpmB+
•Inspect VAD control
solenoid valve
•Inspect related
harness Engine speed
above 5,800
rpmBelow 1.0
—*
7————
4DHO2S (Rear) heater
controlHO2S (Rear)
heaterIgnition switch
ONEngine speed
below 4,000
rpmB+
•Inspect HO2S (Front)
heater.
•Inspect related
harness Engine speed
above 4,000
rpmBelow 1.0
4EEGR valve #1 coil
controlEGR valve
(terminal E)Ignition switch ON Below 1.0•Inspect EGR valve
•Inspect related
harness Idle Below 1.0
4F Cooling fan control Cooling fan relay IdlingECT below 100
°C {212 °F}B+
•Inspect cooling fan
relay
•Inspect related
harness A/C operating
and refrigerant
pressure switch
(middle) ONBelow 1.0
4G IAC (+) IAC valve•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect IAC valve
•Inspect related
harness
4HEGR valve #2 coil
controlEGR valve
(terminal A)Ignition switch ON B+•Inspect EGR valve
•Inspect related
harness Idle B+
4I Starter relay controlStarter relay
(MTX)
TR switch (ATX)Under any condition Below 1.0•Perform “On-Board
Diagnostic Test”
•Inspect related
harness
4J IAC (–)IAC valve•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect IAC valve
•Inspect related
harness
4KEGR valve #3 coil
controlEGR valve
(terminal B)Ignition switch ON B+•Inspect EGR valve
•Inspect related
harness Idle B+
4L Cooling fan control Cooling fan relay IdlingECT below 100
°C {212 °F}B+•Inspect cooling fan
relay
•Inspect related
harness A/C operating Below 1.0
4MOCV control*
5OCV•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect OCV valve
•Inspect related
harness
—*
7————
4NEGR valve #4 coil
controlEGR valve
(terminal F)Ignition switch ON Below 1.0•Inspect EGR valve
•Inspect related
harness Idle Below 1.0
4O A/C A/C relayA/C operating Below 1.0•Inspect A/C relay
•Inspect related
harness A/C not operating B+
4PFuel pump
control*
10Fuel pump relayIgnition switch ON B+•Inspect fuel pump
relay
•Inspect related
harness Cranking Below 1.0
Idle Below 1.0
—*
9———— Terminal Signal Connected to Test conditionVoltage
(V)Action

CONTROL SYSTEM
F1–45
F1
Generator field coil control signal
PCM terminals
•1AD(+)—1C(–)
Oscilloscope setting
•0.5 V/DIV (Y), 1 ms/DIV (X), DC range
Vehicle condition
•Idle after warm up (engine speed approx. 650
rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C
off)
CKP sensor signal
(+)
PCM terminals
•2D(+)—2H(–)
Oscilloscope setting
•2 V/DIV (Y), 4 ms/DIV (X), DC range
Vehicle condition
•Idle after warm up (engine speed approx. 650
rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C
off)
(–)
PCM terminals
•2G(+)—2H(–)
Oscilloscope setting
•2 V/DIV (Y), 4 ms/DIV (X), DC range
Vehicle condition
•Idle after warm up (engine speed approx. 650
rpm [MTX] or 700 rpm [ATX], no load, P/S off, A/C
off)
VSS signal
PCM terminals
•3C(+)—2AC(–)
Oscilloscope setting
•1 V/DIV (Y), 10 ms/DIV (X), DC range
Vehicle condition
•Drive the vehicle with approx. 10 km/h {6.2 mph}
0 V
A6A3940W006
0 V
A6A3940W007
0 V
A6A3940W008
0 V
A6A3940W011

TROUBLESHOOTING
F1–57
F1
ENGINE SYMPTOM TROUBLESHOOTINGA6E398018881201•Confirm trouble symptom using the following diagnostic index, then go to appropriate troubleshooting chart.
Diagnostic Index
End Of Sie
TROUBLESHOOTING
No. TROUBLESHOOTING ITEM DESCRIPTION
1 Melting of main or other fuses—
2 MIL illuminates MIL is illuminated incorrectly.
3 Will not crank Starter does not work.
4Hard to start/long crank/erratic start/erratic
crankStarter cranks engine at normal speed but engine requires excessive
cranking time before starting.
5 Engine stalls. After start/at idle Engine stops unexpectedly at idle and/or after start.
6 Cranks normally but will not start Starter cranks engine at normal speed but engine will not run.
7 Slow return to idle Engine takes more time than normal to return to idle speed.
8 Engine runs rough/rolling idleEngine speed fluctuates between specified idle speed and lower
speed and engine shakes excessively.
9 Fast idle/runs onEngine speed continues at fast idle after warm-up.
Engine runs after ignition switch is turned to off.
10 Low idle/stalls during decelerationEngine stops unexpectedly at beginning of deceleration or recovery
from deceleration.
11Engine stalls/quits. Acceleration/cruiseEngine stops unexpectedly at beginning of acceleration or during
acceleration.
Engine stops unexpectedly while cruising.
Engine runs rough. Acceleration/cruise Engine speed fluctuates during acceleration or cruising.
Misses Acceleration/cruise Engine misses during acceleration or cruising.
Buck/jerkAcceleration/cruise/
decelerationVehicle bucks/jerks during acceleration, cruising, or deceleration.
Hesitation/stumble Acceleration Momentary pause at beginning of acceleration or during acceleration
Surges Acceleration/cruise Momentary minor irregularity in engine output
12 Lack/loss of power Acceleration/cruisePerformance is poor under load.
(e.g., power down when climbing hills)
13 Knocking/pinging Acceleration/cruiseSound is produced when air/fuel mixture is ignited by something other
than spark plug. (e.g., hot spot in combustion chamber)
14 Poor fuel economy Fuel economy is unsatisfactory.
15 Emission compliance Fails emissions test.
16 High oil consumption/leakage Oil consumption is excessive.
17Cooling system
concernsOverheating Engine runs at higher than normal temperature/overheats.
18Cooling system
concernsRuns cold Engine does not reach normal operating temperature.
19 Exhaust smoke Blue, black, or white smoke from exhaust system
20 Fuel odor (in engine compartment) Gasoline fuel smell or visible leakage
21 Engine noise Engine noise from under hood
22 Vibration concerns (engine) Vibration from under hood or driveline
23 A/C does not work sufficiently.A/C compressor magnetic clutch does not engage when A/C is turned
on.
24A/C is always on or A/C compressor runs
continuously.A/C compressor magnetic clutch does not disengage.
25 A/C is not cut off under WOT conditions. A/C compressor magnetic clutch does not disengage under WOT.
26 Exhaust sulphur smell Rotten egg smell (sulphur) from exhaust
27 Constant voltage Incorrect constant voltage
28 Spark plug condition Incorrect spark plug condition
29 ATX concernsUpshift/downshift/
engagementATX concerns not related to engine performance

F1–58
TROUBLESHOOTING
QUICK DIAGNOSTIC CHARTA6E398018881202
X: Applicable
Possible factor
Troubleshooting item
Starter motor malfunction (Mechanical or electrical)
Starter circuit including ignition switch is open.
Starter interlock switch malfunction (MTX with starter
interlock system)
Improper engine oil level
Low or dead battery
Charging system malfunction
Improper engine compression
Improper valve timing
Hydrolocked engine
Improper engine oil viscosity
Improper dipstick
Base engine malfunction
Drive plate or flywheel are seized.
Improper tension or damaged drive belts
Improper engine coolant level
Water and anti-freeze mixture is improper.
Cooling system malfunction (Radiator, hoses,
overflow system, thermostat, etc.)
Cooling fan system malfunction
Engine or transaxle mounts are improperly installed.
Cooling fan or condenser fan seat are improper.
Accelerator cable free play misadjustment
Cruise control cable misadjustment
Fuel quality
1 Melting of main or other fuses2 MIL illuminates x x x x x x x3 Will not crank4 Hard to start/long crank/erratic start/erratic
crankx
5 Engine stalls. After start/at idle x x x x6 Cranks normally but will not start x x x x7 Slow return to idlex8 Engine runs rough/rolling idle x x x9 Fast idle/runs onxx10 Low idle/stalls during decelerationEngine stalls/quits. Acceleration/cruise x x xEngine runs rough. Acceleration/cruise x x xMissesAcceleration/cruise x x xBuck/jerk Acceleration/cruise/
decelerationxx x
Hesitation/stumble Acceleration x x x
11
Surges Acceleration/cruis
exx x12 Lack/loss of powerAcceleration/cruisexx x13 Knocking/pingingAcceleration/cruisexx14 Poor fuel economy x x x x x x15 Emission compliance x x x x16 High oil consumption/leakage x x x17 Cooling system concerns Overheatingxx x x x18 Cooling system concernsRuns cold x x19 Exhaust smoke x x x20 Fuel odor (in engine compartment)21 Engine noise x x x22 Vibration concerns (engine) x x x23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smellx27 Constant voltage28 Spark plug condition x x29 ATX concernsUpshift/downshift
engagementSee Section K, TROUBLESHOOTING
A6E39802001

TROUBLESHOOTING
F1–59
F1
X: Applicable
Possible factor
Troubleshooting itemVariable valve timing system malfunction (L3 engine
model)
VICS malfunction
Engine overheating
Air cleaner element clogging or restriction
Air leakage from intake-air system (Loose tubes,
cracks, gaskets breakage)
IAC valve improper operation
Throttle body malfunction
VICS malfunction (L3 engine model)
VACS malfunction (L3 engine model)
Vacuum leakage (Vacuum hose damage, misrouting)
Ignition coil malfunction (e.g. open, short or cracks)
Initial ignition timing misadjustment (CKP sensor &
crankshaft pulley misadjustment)
Spark plug malfunction
High-tension leads malfunction (Cracks, open, low
resistance)
CKP sensor is damaged. (e.g. open or short circuits )
Crankshaft pulley is damaged
Improper gap between CKP sensor and crankshaft
Fuel pump malfunction (Mechanically or electrically)
Pressure regulator malfunction
Fuel hoses restriction or clogging
1 Melting of main or other fuses2 MIL illuminates x x x x x3 Will not crank4 Hard to start/long crank/erratic start/erratic
crankx x x x x x xxxxxx
5 Engine stalls. x x x x x xxxxxxxxxxx6 Cranks normally but will not start x x x x xxxxxxxxxxx7 Slow return to idle x8 Engine runs rough/rolling idle x x x x x x x x xxxxxxx9 Fast idle/runs on x x10 Low idle/stalls during deceleration x x xEngine stalls/quits. Acceleration/cruise x x x x x x x x xxxxxxxEngine runs rough. Acceleration/cruise x x x x x x x x xxxxxxxMissesAcceleration/cruise x x x x x x x x xxxxxxxBuck/jerk Acceleration/cruise/dece
lerationxxx x xx x x x xxxxxx
Hesitation/stumble Acceleration x x x x x x x x xxxxxxx
11
Surges Acceleration/cruise x x x x x x x x xxxxxxx
12 Lack/loss of powerAcceleration/cruise x x x x x x x x xxxxxxx13 Knocking/pingingAcceleration/cruise x x x14 Poor fuel economy x x x x x x x15 Emission compliance x x x x x x x x x16 High oil consumption/leakage17 Cooling system
concernsOverheating
18 Cooling system
concernsRuns cold
19 Exhaust smoke x x x x x x20 Fuel odor (in engine compartment)x21 Engine noise x x x22 Vibration concerns (engine)23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smell x x x x27 Constant voltage28 Spark plug condition x x x x x x29 ATX concernsUpshift/downshift
engagementSee Section K, TROUBLESHOOTING
A6E39802002

F1–60
TROUBLESHOOTING
X: Applicable
Possible factor
Troubleshooting item
Injectors malfunction (Leakage or clogging, inope-rative
Fuel leakage from fuel system (including insulator,
injector O-ring)
Fuel filters restriction or clogging
CMP sensor is damaged. (e.g. open or short circuit)
Camshaft is damaged.
Improper air/fuel mixture ratio control
Exhaust system restriction or clogging
Catalytic converter malfunction
EGR system malfunction (Unleaded gasoline models)
EVAP control system malfunction
PCV valve malfunction
Constant voltage supply circuit malfunction
Main relay malfunction (Mechanically or electrically)
ECT sensor malfunction
TR sensor misadjustment (ATX)
TR sensor malfunction (ATX)
Break switch and related circuit malfunction
Manifold absolute pressure sensor and related circuit
malfunction
HO2S and related circuit malfunction (Unleaded
gasoline models)
Variable resistor misadjustment (Leaded gasoline
models)
Improper electrically controlled 4WD system operation
1 Melting of main or other fuses2 MIL illuminates x x x x x x x3 Will not crankxx4 Hard to start/long crank/erratic start/erratic
crankx xx xxx x
5 Engine stalls. After start/at idle x x x x x x x x x6 Cranks normally but will not start x x x xxxxxx x7 Slow return to idlex8 Engine runs rough/rolling idle xxxxxx xxx x9 Fast idle/runs onx10 Low idle/stalls during deceleration x x x x xEngine stalls/quits.Acceleration/cruisex xxxxx xxxxx xEngine runs rough. Acceleration/cruisex xxxxx xxxxx xMissesAcceleration/cruisex xxxxx xxxxx xBuck/jerk Acceleration/cruise/
decelerationx xxxxx xxxxx x
Hesitation/stumble Acceleration xxxxxx xxxxx x
11
Surges Acceleration/cruise xxxxxx xxxxx x
12 Lack/loss of power Acceleration/cruise x x x x x x x x13 Knocking/pingingAcceleration/cruise x14 Poor fuel economy x x x x x x15 Emission compliancexxxxxxxxx x16 High oil consumption/leakage x17 Cooling system concerns Overheating18 Cooling system concernsRuns cold19 Exhaust smoke x x20 Fuel odor (in engine compartment) x x21 Engine noise22 Vibration concerns (engine)x23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smell x x27 Constant voltage x x x x x28 Spark plug condition x x x x29 ATX concernsUpshift/downshift/en
gagementSee Section K, TROUBLESHOOTING
A6E39802003

TROUBLESHOOTING
F1–61
F1
End Of Sie
X: Applicable
Possible factor
Troubleshooting itemIAT sensor and related circuit malfunction
Barometric pressure sensor malfunction
Neutral or clutch switch and related circuit
malfunction (MTX)
MAF sensor and related circuit malfunction
Knock sensor and related circuit malfunction
TP sensor and related circuit malfunction
TP sensor misadjustment (including looseness)
P/S pressure switch and related circuit
malfunction
Improper refrigerant charging amount
A/C relay (A/C control signal circuit malfunction
A/C compressor magnetic clutch malfunction
Condenser fan system malfunction
Improper load signal input
Clutch slippage
ATX related parts malfunction
VSS and related circuit malfunction
Improper ATF level
Brake dragging
Loose parts
Improper balance of wheels and tires
Drive line malfunction
Suspension malfunction
PATS operating (if equipped)
1 Melting of main or other fuses2 MIL illuminates x x x x x x x x3 Will not crankx4 Hard to start/long crank/erratic
start/erratic crankx
5 Engine stalls. After start/at idle x x x x6 Cranks normally but will not startx7 Slow return to idle8 Engine runs rough/rolling idle x x x x x x9 Fast idle/runs onx10 Low idle/stalls during deceleration x x x x x xEngine stalls/quits.Acceleration/cruisex x xx xx xxxEngine runs rough. Acceleration/cruisex x xx xx xxxMissesAcceleration/cruisex xx xx xxxBuck/jerk Acceleration/cruise
/decelerationx xx xx xxx
Hesitation/stumble Acceleration x x x x x x x x x
11
Surges Acceleration/cruise x x x x x x x x
12 Lack/loss of power Acceleration/cruise x x x x x x x x13 Knocking/pingingAcceleration/cruise x x x14 Poor fuel economy x x x x x15 Emission compliance x16 High oil consumption/leakage17 Cooling system
concernsOverheating x x x
18 Cooling system
concernsRuns cold x
19 Exhaust smoke20 Fuel odor (in engine compartment)21 Engine noisex22 Vibration concerns (engine)xxxx23 A/C does not work sufficiently. x x x24 A/C is always on or A/C compressorruns continuously.xx25 A/C is not cut off under WOT conditions x x26 Exhaust sulfur smell27 Constant voltage x x x x x x28 Spark plug condition x x29 ATX concernsUpshift/downshift/e
ngagementSee Section K, TROUBLESHOOTING
A6E39802004

TROUBLESHOOTING
F1–63
F1
End Of Sie
4 Is strong blue spark visible at each disconnected
high-tension lead while cranking engine?Yes Inspect for following:
•Spark plugs malfunction
•CMP sensor is improperly installed.
•Trigger wheel damage on camshaft
•Open or short circuit on CMP sensor
•Open or short circuit between CMP sensor and
PCM terminal 2J or 2M
Repair or replace malfunctioning parts.
If okay, go to next step.
No Inspect following:
•High-tension leads
•Ignition coil and connector
5 Install fuel pressure gauge between fuel pipe
and fuel distributor.
Start engine and run it at idle.
Measure fuel line pressure at idle.
Is fuel line pressure correct at idle?Yes Go to next step.
NoZero or low:
Inspect for clogged fuel line.
If okay, replace fuel pump unit
High:
Replace fuel pump unit.
6 Inspect for VTCS operation.
Does VTCS work properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
7Note
•The following test should be performed for
vehicles with variable valve timing control
system. Go to next step for vehicles
without variable valve timing control
system.
Inspect for variable valve timing control system
operation.
Does variable valve timing control system work
properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
8Note
•The following test should be performed for
vehicles with VIS. Go to next step for
vehicles without VIS.
Inspect for VIS operation.
Does VIS work properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
9 Remove and shake PCV valve.
Does PCV valve rattle?Yes Go to next step.
No Replace PCV valve.
10 Inspect for restriction in the exhaust system.
Is there any restriction?Yes Inspect exhaust system.
No Go to next step.
11 Inspect for contaminated MAF sensor.
Is there any contamination?Yes Go to next step.
No Inspect for cause.
12 Inspect MAF sensor for contamination.
Is there any contamination?Yes Replace MAF sensor.
No Go to Step 14. (2WD)
Go to next step. (4WD)
13 Inspect electrically controlled 4WD system
operation.
Is operation of electrically controlled 4WD
system okay?Yes Go to next step.
No Repair or replace malfunctioning parts.
14 Is engine compression correct? Yes Inspect valve timing.
No Inspect for cause.
15 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. STEP INSPECTION RESULTS ACTION