6E-354 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
15
Check items that can cause the engine to run lean. Refer to
DTC P0171 "O2 Sensor System Too Lean (Bank 1)" or DTC
P0174 "O2 Sensor System Tool Lean (Bank 2)".
Was a problem found?
- Verify repair Go to Step 16
16
Check for proper ignition voltage output with the spark tester.
Was a problem found?
- Verify repair Go to Step 17
17
Check the ignition coils for cracks or carbon tracking. If a
problem is found, repair as necessary.
Was a problem found?
- Verify repair Go to Step 18
18
1. Remove the spark plugs and check for gas or oil fouling
cracks, wear, improper gap, burned electrodes, heavy
deposits, or improper heat range.
2. If spark plugs are fouled, the cause of fouling must be
determined before replacing the spark plugs.
Was a problem found?
- Verify repair Go to Step 19
19
Visually/physically check the vacuum hose for splits, kinks and
proper connections and routing.
Was a problem found?
- Verify repair Go to Step 20
20
Check the exhaust system for a possible restriction:
Damaged or collapsed pipes.
Internal muffler failure.
Was a problem found?
- Verify repair Go to Step 21
21
Check the torque converter clutch (TCC) for proper operation
(if A/T model). If a problem is found, repair as necessary.
Was a problem found?
- Verify repair Go to Step 22
22
Check for the following engine mechanical problems (refer to
Engine Mechanical Section):
Low compression.
Leaking cylinder head gaskets.
Worn camshaft.
Sticking or leaking valves.
Valve timing.
Broken valve springs.
Camshaft drive belt slipped or stripped.
Was a problem found?
- Verify repair Go to Step 23
23
1. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no malfunctions
have been found, review/inspect the following:
Visual/physical inspection.
Tech 2 data.
All electrical connections within a suspected circuit and/or
system.
Was a problem found?
- Verify repair Go to Step 24
6E-356 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DETONATION/SPARK KNOCK SYMPTOM
DEFINITIONS: A mild to sever ping, usually worse
under acceleration. The engine makes a shape metallic
knocking sound that changes with throttle opening.
Prolonged detonation may lead to complete engine
failure.
Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go to On Board
Diagnostic (OBD)
System Check
2
1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
- Verify repair Go to Step 3
3
Was a visually/physical check performed?
- Go to Step 4 Go to Visual /
physical Check.
4
1. If Tech 2 readings are normal (refer to Typical Scan
Data Values) and there are no engine mechanical
faults, fill the fuel tank with a known quality
gasoline.
2. Re-evaluate the vehicle performance.
Is detonation present?
- Go to Step 5
Verify repair
5
Check for obvious overheating problems:
Low engine coolant.
Restricted air flow to radiator.
Incorrect coolant solution.
If a problem is found, repair as necessary.
Was a problem found?
- Verify repair Go to Step 6
6
1. Using a Tech 2, display the ECT sensor and IAT
sensor value.
2. Check the specified value or wire.
Was the problem found?
- Verify repair Go to Step 7
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-357
Step Action Value (s) Yes No
7
1. Using the Tech 2, ignition "On" and engine "On".
2. Monitor the "Mass Air Flow" in the data display.
Does the Tech 2 indicate correct "Mass Air Flow" as
shown in the following graph, when engine speed is
increasing little by little?
Characteris tic of MAF Sens or -Ref erence (No Engine Load)-
0 5 10 15 20 25 30 35 40 45 50
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000
Eng i ne Speed ( r pm) ( T ech2 R eadi ng )
Mass Air Flow (g/s)
( T ec h2 R eadi ng)
- Go to Step 9 Go to Step 8
8
Remove the MAF & IAT sensor assembly and check
for the following conditions.
Objects blocking the air cleaner.
Objects blocking the MAF sensor.
Objects blocking the throttle valve.
Vacuum leaking at intake duct.
Vacuum leaking at throttle body.
If a problem is found, repair as necessary.
Was the problem found?
- Verify repair Refer to DTC
P0101 and Go to
Step 9
9
1. Using the Tech 2, ignition "On" and engine "Off".
2. Monitor the "Throttle Position" in the data display.
Does the Tech 2 indicate correct "Throttle Position"
from 0% to 100% depending on accelerator pedal
operation?
- Go to Step 11 Go to Step 10
10
1. Using the Tech 2, ignition "On" and engine "Off".
2. Monitor the "Throttle Position" in the data display.
3. Adjust the accelerator cable or TPS within 0% to
100%.
Is the action complete?
- Verify repair -
11
Check the fuel control Heated Oxygen Sensor
(HO2S). When monitored on the Tech 2, the HO2S
should respond quickly to different throttle positions. If
it doesn't check for silicon or other contaminates from
fuel or use of improper sealant. The sensors may have
a white powdery coating. Silicon contamination sends
a rich exhaust signal which causes the ECM to
command and excessively lean air/fuel mixture.
Was a problem found?
- Verify repair Go to Step 12
6E-358 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
12
Check the fuel pressure. Refer to Fuel System
Diagnosis.
Was a problem found?
- Verify repair Go to Step 13
13
Monitor "B1S1 (Bank 1 Sensor 1) Status" and "B2S1
(Bank 2 Sensor 1) Status" on the Tech 2.
Is the "B1S1 (Bank 1 Sensor 1) Status" or "B2S1
(Bank 2 Sensor 1) Status" in the lean condition?
- Go to Step 14 Go to Step 15
14
Check items that can cause the engine to run lean.
Refer to DTC P0171 "O2 Sensor System Too Lean
(Bank 1)" or DTC P0174 "O2 Sensor System Tool
Lean (Bank 2)".
Was a problem found?
- Verify repair Go to Step 15
15
Check spark plugs for proper heat range.
Were incorrect spark plugs installed?
- Verify repair Go to Step 16
16
1. Remove excessive carbon buildup with a top
engine cleaner.
2. Re-evaluate vehicle performance.
Is detonation still present?
- Verify repair Go to Step 17
17
Check for an engine mechanical problem. Perform a
cylinder compression check. Refer to Engine
Mechanical.
Was a problem found?
- Verify repair Go to Step 18
18
1. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no
malfunctions have been found, review/inspect the
following:
Visual/physical inspection.
Tech 2 data.
All electrical connections within a suspected circuit
and/or system.
Was a problem found?
- Verify repair Go to Step 19
19
Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the "SPS (Service Programming System)".
Was the problem solved?
- Verify repair Go to Step 20
20
Replace the ECM.
Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual. Following
ECM programming, the immobilizer system (if
equipped) must be linked to the ECM. Refer to section
11 “Immobilizer System-ECM replacement” for the
ECM/Immobilizer linking procedure.
- Verify repair -
6E-360 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
11
1. Using a Tech 2, display the ECT sensor and IAT
sensor value.
2. Check the specified value or wire.
Was the problem found?
- Verify repair Go to Step 12
12
1. Remove the spark plugs and check for gas or oil
fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must
be determined before replacing the spark plugs.
Was a problem found?
- Verify repair Go to Step 13
13
Check for proper calibration of the speedometer.
Does the speed indicated on the speed meter closely
match the vehicle speed displayed on the Tech 2?
- Go to Step 15 Go to Step 14
14
Diagnose and repair the inaccurate speedometer
condition as necessary. Refer to Vehicle Speed
Sensor in Electrical Diagnosis.
- Verify repair -
15
Check for proper calibration of the fuel gauge.
Was a problem found?
- Verify repair Go to Step 16
16
Check for the following engine mechanical problems
(refer to Engine Mechanical):
Low compression.
Worn camshaft.
Sticking or leaking valves.
Valve timing.
Was a problem found?
- Verify repair Go to Step 17
17
1. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no
malfunctions have been found, review/inspect the
following:
Visual/physical inspection.
Tech 2 data.
All electrical connections within a suspected circuit
and/or system.
Was a problem found?
- Verify repair Go to Step 18
18
Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the "SPS (Service Programming System)".
Was the problem solved?
- Verify repair Go to Step 19
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-363
Step Action Value (s) Yes No
14
Check the EVAP purge solenoid valve operation.
Is the valve operated normally?
- Verify repair &
Go to Step 17 Verify repair &
Go to Step 15
15
Check the exhaust system for a possible restriction:
Damaged or collapsed pipes.
Internal catalytic converter failure.
Was a problem found?
- Verify repair &
Go to Step 17 Go to Step 16
16
1. Remove excessive carbon buildup with a top
engine cleaner. Refer to the instructions on the top
engine cleaner can.
2. Perform the exhaust emission test.
Does the vehicle pass the test?
- System OK Go to Step 18
17
Perform the exhaust emission test.
Does the vehicle pass the test?
- System OK Go to Step 18
18
Check the fuel control Heated Oxygen Sensor
(HO2S). When monitored on the Tech 2, the HO2S
should respond quickly to different throttle positions. If
it doesn't check for silicon or other contaminates from
fuel or use of improper sealant. The sensors may have
a white powdery coating. Silicon contamination sends
a rich exhaust signal which causes the ECM to
command and excessively lean air/fuel mixture.
Was a problem found?
- Verify repair Go to Step 19
19
Monitor "B1S1 (Bank 1 Sensor 1) Status" and "B2S1
(Bank 2 Sensor 1) Status" on the Tech 2.
Is the "B1S1 (Bank 1 Sensor 1) Status" or "B2S1
(Bank 2 Sensor 1) Status" in the rich condition?
- Go to Step 20 Go to Step 21
20
Check items that can cause the engine to run rich.
Refer to DTC P0172 "O2 Sensor System Too Rich
(Bank 1)" or DTC P0175 "O2 Sensor System Too Rich
(Bank 2)".
Was a problem found?
- Verify repair Go to Step 22
21
Check items that can cause the engine to run lean.
Refer to DTC P0171 "O2 Sensor System Too Lean
(Bank 1)" or DTC P0174 "O2 Sensor System Tool
Lean (Bank 2)".
Was a problem found?
- Verify repair Go to Step 22
22
Check for the following engine mechanical problems
(refer to Engine Mechanical):
Low compression.
Leaking cylinder head gaskets.
Worn camshaft. -Sticking or leaking valves.
Valve timing. -Broken valve springs.
Was a problem found?
- Verify repair Go to Step 23
6E-366 3.5L ENGINE DRIVEABILITY AND EMISSIONS
BACKFIRE SYMPTOM
DEFINITIONS: Fuel ignites in the intake manifold, or in
the exhaust system, making a loud popping noise.
Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go to On Board
Diagnostic (OBD)
System Check
2
1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
- Verify repair Go to Step 3
3
Was a visually/physical check performed?
- Go to Step 4 Go to Visual /
physical Check.
4
Check for proper ignition voltage output with the spark
tester.
Was a problem found?
- Verify repair Go to Step 5
5
Check the ignition coils for cracks or carbon tracking.
If a problem is found, repair as necessary.
Was a problem found?
- Verify repair Go to Step 6
6
1. Remove the spark plugs and check for gas or oil
fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must
be determined before replacing the spark plugs.
Was a problem found?
- Verify repair Go to Step 7
7
Check the fuel pressure. Refer to Fuel System
Pressure Test.
Was a problem found?
- Verify repair Go to Step 8
8
Refer to 6E-116 page Fuel System Diagnosis to
determine if there is a problem with fuel delivery.
Was a problem found?
- Verify repair Go to Step 9
9
Check the CKP sensor signal, shield wire, or
installation condition. Refer to DTC P0336 "Crankshaft
Position Sensor Circuit Range/Performance" and DTC
P0337 "Crankshaft Position Sensor Circuit No Signal".
Was a problem found?
- Verify repair Go to Step 10
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-369
CRANKSHAFT POSITION (CKP)
SENSOR
Location
Right-hand side of the cylinder block.
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect connector from the CKP sensor.
3. Loosen a bolt and remove the CKP sensor from
the cylinder block.
NOTE:
Use caution to avoid any hot oil that might drip out.
Installation Procedure
1. Install the CKP sensor to the cylinder block.
Before installation, apply small amount of engine
oil to the O-ring.
2. Tighten CKP sensor by a bolt with specified
tightening torque.
Tightening Torque
Bolt: 10N
m (1.0kgf
m).
3. Connect a sensor connector to the CKP sensor.
4. Connect the negative battery cable.
NOTE:
Verify any DTCs (diagnosis Trouble Code) are not
stored after replacement.
CAMSHAFT POSITION (CMP)
SENSOR
Location
The rear of right bank of the cylinder head.
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect connector from the CMP sensor.
3. Loosen a bolt and remove the CMP sensor from
the cylinder head.
Installation Procedure
1. Install the CMP sensor to the cylinder head.
Before installation, apply small amount of engine
oil to the O-ring.
2. Tighten CMP sensor by a bolt with specified
tightening torque.
Tightening Torque
Bolt: 10N
m (1.0kgf
m)
3. Connect a sensor connector to the CMP sensor.
4. Connect the negative battery cable.
NOTE:
Verify any DTCs (diagnosis Trouble Code) are not
stored after replacement.