6E±79
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
3.5L V-6 Engine (Automatic and Manual Transmission)
Tech 2
Parameter
Data ListUnits DisplayedTypical Data
Values (IDLE)Typical Data
Values
(2500 RPM)Refer To
A/C Clutch
RelayEngineOn/OffOffOffGeneral Description and
Operation, A/C Clutch
Circuit Operation
A/C RequestEngineYes/NoNoNoGeneral Description and
Operation, A/C Request
Signal
Air/Fuel RatioEngineRatio: _ to 114.714.7General Description and
Operation, Fuel System
Metering Purpose
APP Sensor1EnginePercent11±1335±40General Description and
Operation
APP Sensor2EnginePercent87±8860±65General Description and
Operation
APP Sensor3EnginePercent87±8850±57General Description and
Operation
Barometric
PressureEnginekPa61-104
(depends on
altitude and
barometric
pressure)61-104
(depends on
altitude and
barometric
pressure)General Description and
Operation
Brake Light
SwitchEngineOpen 0V/Closed
12VOpen 0VOpen 0VRefer to Section 5
Check Trans
Lamp (Auto
Trans)EngineOn/OffOffOff4L30-E Automatic
Transmission Diagnosis
Cruise Main
SwitchEngineActive/InactiveInactiveInactiveRefer to Section 10
Cruise Set
SwitchEngineActive/InactiveInactiveInactiveRefer to Section 10
Cruise Cancel
SwitchEngineActive/InactiveInactiveInactiveRefer to Section 10
Cruise
Resume
SwitchEngineActive/InactiveInactiveInactiveRefer to Section 10
Decel Fuel
CutoffEngineActive/InactiveInactiveInactiveGeneral Description and
Operation, Deceleration
Mode
Desired EGR
PositionEnginePercent0%0%General Description and
Operation, EGR Pintle
Position Sensor
Desired Idle
SpeedEngineRPM750800General Description and
Operation
ECT (Engine
Coolant Temp)EngineDegrees C,
Degrees F80-100C
(176-212F)80-100C
(176-212F)General Description and
Operation, Engine
Coolant Temperature
(ECT) Sensor
EGR Closed
Pintle PositionEngineSteps20-4020-40General Description and
Operation, EGR Pintle
Position Sensor
6E±83
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Tech 2
ParameterRefer To Typical Data
Values
(2500 RPM) Typical Data
Values (IDLE) Units Displayed Data List
Spark
(Advance)EngineDegrees Before
Top Dead Center15-2234-44General Description and
Operation, Electronic
Ignition System
Start-Up ECT
(Engine
Coolant Temp)EngineDegrees C,
Degrees FDepends on
engine coolant
temperature at
time of start-upDepends on
engine coolant
temperature at
time of start-upGeneral Description and
Operation, Engine
Coolant Temperature
(ECT) Sensor
Start-Up IAT
(Intake Air
Temp)EngineDegrees C,
Degrees FDepends on
intake air
temperature at
time of start-upDepends on
intake air
temperature at
time of start-upGeneral Description and
Operation, Intake Air
Temperature (IAT) Sensor
TCC Cruise
Brake SwitchEngineActive/InactiveActiveActiveRefer to Section 10
Total Misfire
Current CountMisfireCounts0-50-5DTC P0300
TP Sensor 1
(Throttle
Position
Sensor 1)EnginePercentage8±1228±36General Description and
Operation, Throttle
Position (TP) Sensor
TP Sensor 2
(Throttle
Position
Sensor 2)EnginePercentage8±1228±36General Description and
Operation, Throttle
Position (TP) Sensor
Throttle at IdleEngineNo/YesYe sNoGeneral Description and
Operation, Throttle
Position (TP) Sensor
Upshift Lamp
(manual trans)EngineOn/OffOffOffManual Transmission
Vehicle SpeedEngineMPH / km/h004L30-E Automatic
Transmission Diagnosis
Weak CylinderMisfireCylinder #ÐÐDTC P0300
6E±102
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Circuit Description
The electronic Ignition system uses a coil -at-plug method
of spark distribution. In this type of ignition system, the
powertrain control module (PCM) triggers the correct
driver outside the Ignition Current Sense System (ICSS),
which then triggers the correct ignition coil based on the
58X signal received from the crankshaft position sensor
(CKP). The spark plug connected to the coil fires when
the ICSS opens the ground circuit for the coil's primary
circuit.
During crank, the PCM monitors the CKP 58X signal. The
CKP signal is used to determine which cylinder will fire
first. After the CKP 58X signal has been processed by the
PCM, it will command all six injectors to allow a priming
shot of fuel for all the cylinders. After the priming, the
injectors are left ªOFFº during the next six 58X reference
pulses from the CKP. This allows each cylinder a chance
to use the fuel from the priming shot. During this waiting
been received by the PCM. The ION sensor signal allows
the PCM to operate the injectors sequentially based on
camshaft position. If the camshaft position signal is not
present at start - up, the PCM will begin sequential fuel
delivery with a 1 -in-6 chance that fuel delivery is correct.
The engine will run without a ION sensor signal, but will
set a DTC code.
Diagnostic Aids
An intermittent problem may be caused by a poor
connection, rubbed - through wire insulation or a wire
broken inside the insulation. Check for the following
items:
Poor connection or damaged harness-Inspect the
PCM harness and connectors for improper mating,
broken locks, improperly formed or damaged
terminals, poor terminal-to-wire connection, and
damaged harness.
Faulty engine coolant temperature sensor-Using a
Tech 2, compare engine coolant temperature with
intake air temperature on a completely cool engine.
Engine coolant temperature should be within 10 C of
intake air temperature. If not, replace the ECT sensor.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
5. An obvious cause of low fuel pressure would be an
empty fuel tank.
6. The engine will easily start and run if a few injectors
are disabled. It is not necessary to test all injectors
at this time since this step is only a test to verify that
all of the injectors have not been disabled by fuel
contamination.
7. A blinking test light verifies that the PCM is
monitoring the 58X crankshaft reference signal and
is capable of activating the injectors. If there is an
open or shorted driver circuit, DTCs 201 ± 206 and
a misfire DTC 300 ± 306 should be set.
19. By using a spark tester, each ignition coil's ability to
produce 25,000 volts is verified.
25. If there is an open or shorted driver circuit, DTCs
201 ± 206 and a misfire DTC 301 ± 306 should be
set. All six injector driver circuits can be checked at
one time without removing the intake manifold if a J
39021 ± 95 test light is available. This is the
alternative procedure:
With the ignition ªOFFº, disconnect the gray
connector located at the rear of the air filter, attached
to a bracket on the purge canister.
Connect test light J 39021 ± 95 to the connector. Do
any of the light constantly illuminate or fail to blink
when the engine is cranked? If so, repair the short or
open circuit, or replace the PCM if indicated.
This procedure only tests the driver circuit as far as the
test connection, so step 31 is added to test the circuit all
the way to the injector.
Engine Cranks But Will Not Run
StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Check the ignition coil fuse, the engine fuse, and the
PCM fuse.
Was a fuse blown?
ÐGo to Step 3Go to Step 4
3Check for a short to ground and replace the fuse.
Is the action complete?
ÐVerify repairÐ
6E±124
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Evaporative (EVAP) Emissions Canister Purge Valve Check
060RY00398
Circuit Description
Canister purge is controlled by a solenoid valve that
allows manifold vacuum to purge the canister. The
powertrain control module (PCM) supplies a ground to
energize the solenoid valve (purge ªONº). The EVAP
purge solenoid control is turned ªONº and ªOFFº several
times a second. The duty cycle (pulse width or ªONº time)
is determined by engine operating conditions including
load, throttle position, coolant temperature and ambient
temperature. The duty cycle is calculated by the PCM
and the purge solenoid is enabled when the appropriate
conditions have been met:
The engine run time after start is more than 60
seconds.
The engine coolant temperature is above 30C
(86F).
The fuel control system is operating in the closed-loop
mode.
Diagnostic Aids
Make a visual check of vacuum hoses.
Check the throttle body for cracks.
Check the malfunction indicator lamp for a possible
mechanical problem.
Test Description
The number(s) below refer to the step number(s) on the
Diagnostic Chart.
1. Check to see if the solenoid is open or closed. The
solenoid is normally de-energized in this step, so it
should be closed.
2. This step checks to determine if the solenoid was
open due to an electrical circuit problem or a
defective solenoid.
3. This should normally energize the solenoid, opening
the valve and allowing the vacuum to drop (purge
ªONº).
6E±155
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0117 ECT Sensor Circuit Low Voltage
D06RY00148
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted on a coolant crossover pipe at the
front of the engine. The powertrain control module (PCM)
applies a voltage (about 5 volts) through a pull-up resistor
to the ECT signal circuit. When the engine coolant is cold,
the sensor (thermistor) resistance is high, therefore the
PCM will measure a high signal voltage. As the engine
coolant warms, the sensor resistance becomes lower,
and the ECT signal voltage measured at the PCM drops.
With a fully warmed-up engine, the ECT signal voltage
should measure about 1.5 to 2.0 volts.
Conditions for Setting the DTC
Engine running time is longer than 120 seconds.
The ECT sensor signal indicates an engine coolant
temperature greater than 150C (302F) (about 0.10
V) for a total of 50 seconds over a 100±second period.
Action Taken When the DTC Sets
The PCM will ON the MIL after second trip with
detected fault.
The PCM will substitute the ECT reading with a default
engine coolant temperature value. The default value
is based on start-up intake air temperature and running
time.
The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.
A history DTC P0117 will clear after 40 consecutive
warm-up cycles have occurred without a fault.
DTC P0117 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:
Poor connection at PCM ± Inspect harness connectors
for backed-out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal-to-wire connection.
Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
ECT display on the Tech 2 while moving connectors
and wiring harnesses related to the ECT sensor. A
change in the ECT display will indicate the location of
the fault.
If DTC P0117 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC P1114 Diagnostic Chart may isolate
the cause of the fault.
6E±156
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Verifies that the fault is present.
3. If DTC P0117 can be repeated only by duplicating
the Failure Records conditions, refer to the
ªTemperature vs. Resistance Valuesº table. The
table may be used to test the ECT sensor at various
temperatures to evaluate the possibility of a
ªshiftedº sensor that may be shorted above or below
a certain temperature. If this is the case, replace
the ECT sensor. If the ECT sensor appears to be
OK, the fault is intermittent; refer to
Diagnostic Aids.
Engine Coolant Temperature Sensor
CFOHMS
Temperature vs. Resistance Values
(approximate)
100212177
80176332
60140667
4511 31188
35951802
25772796
15594450
5417280
±52312300
±15521450
±30±2252700
±40±40100700
6E±158
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0118 ECT Sensor Circuit High Voltage
060R200053
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted in on a coolant crossover pipe at the
front of the engine. The powertrain control module (PCM)
applies a voltage (about 5 volts) through a pull-up resistor
to the ECT signal circuit. When the engine coolant is cold,
the sensor (thermistor) resistance is high, therefore the
PCM will measure a high signal voltage. As the engine
coolant warms, the sensor resistance becomes less, and
the ECT signal voltage measured at the PCM drops. With
a fully warmed-up engine, the ECT signal voltage should
measure about 1.5 to 2.0 volts.
Conditions for Setting the DTC
Engine running time is longer than 90 seconds.
The ECT sensor signal indicates an engine coolant
temperature of ±39C (±38F) or less (about 5 volts)
for a total of 50 seconds over a 100-second period.
Action Taken When the DTC Sets
The PCM will ON the MIL after second trip with
detected fault.
The PCM will substitute the ECT reading with a default
engine coolant temperature value. The default value
is based on start-up intake air temperature and running
time.
The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.
A history DTC P0118 will clear after 40 consecutive
warm-up cycles have occurred without a fault.
DTC P0118 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:
The ECT shares a ground with the Transmission Fluid
Temperature sensor, the Fuel Tank Pressure sensor, and
the MAP sensor.
Check the ground if these DTCs are also set.
Poor connection at PCM ± Inspect harness connectors
for backed-out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal-to-wire connection.
Damaged harness ± Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
ECT display on the Tech 2 while moving connectors
and wiring harnesses related to the ECT sensor. A
change in the ECT display will indicate the location of
the fault.
If DTC P0118 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
If it is determined that the DTC occurs intermittently,
6E±159
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
performing the DTC P1115 Diagnostic Chart may isolate
the cause of the fault.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Verifies that the fault is present.
3. If DTC P0118 can be repeated only by duplicating
the Failure Records conditions, refer to the
ªTemperature vs. Resistance Valueº table. The
table may be used to test the ECT sensor at various
temperatures to evaluate the possibility of a
ªshiftedº sensor that may be shorted above or below
a certain temperature. If this is the case, replace
the ECT sensor. If the ECT sensor appears to be
OK, the fault is intermittent; refer to
Diagnostic Aids.
Engine Coolant Temperature Sensor
CFOHMS
Temperature vs. Resistance Values
(approximate)
100212177
80176332
60140667
4511 31188
35951802
25772796
15594450
5417280
±52312300
±15521450
±30±2252700
±40±40100700
DTC P0118 ± ECT Sensor Circuit High Voltage
StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªONº, engine ªOFFº.
2. Observe the ªEng Cool Tempº display on the Tech 2.
Is the ªEng Cool Tempº below the specified value?
±39C
(±38F)
Go to Step 4Go to Step 3
31. Ignition ªONº, engine ªOFFº.
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor the ªDTCº info for DTC
P0118.
Does the Tech 2 indicate DTC P0118 failed?
Ð
Refer to Test
Description
Refer to
Diagnostic
Aids
41. Disconnect the ECT sensor electrical connector.
2. Jumper the ECT signal circuit and the sensor
ground circuit together at the ECT sensor harness
connector.
3. Observe the ªEng Cool Tempº display on the Tech 2.
Is the ªEng Cool Tempº at the specified value?
140C
(284F)
Go to Step 6Go to Step 5
51. Jumper the ECT signal circuit at the ECT sensor
harness connector to chassis ground.
2. Observe the ªEng Cool Tempº display on the Tech 2.
Is the ªEng Cool Tempº at the specified value?
140C
(284F)
Go to Step 7Go to Step 8
6Check for poor connections at the ECT sensor and
replace terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 10