6E-70 3.5L ENGINE DRIVEABILITY AND EMISSIONS
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 systems is new.
Fuel additives such as “dry gas" and “octane
enhancers" may affect the performance of the fuel. The
Reed 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 Reed Vapor Pressure could sho
w
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 your vehicle
may cause driveability problems. Many of the majo
r
fuel companies advertise that using “premium" gasoline
will improve the performance of your vehicle. Mos
t
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 diagnostics have been calibrated to run
with OEM parts.
Aftermarket electronics, such as cellular phones,
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).
Vehicle Marshaling
The transportation of new vehicles from the assembly
plant to the dealership can involve as many as 60 key
cycles within 5Km miles of driving. This type o
f
operation contributes to the fuel fouling of the spark
plugs and will turn on the MIL (“Check Engine" lamp).
Poor Vehicle Maintenance
The sensitivity of OBD diagnostics will cause the MIL
(“Check Engine" lamp) to turn on if the vehicle is no
t
maintained properly. Restricted air filters, fuel filters,
and crankcase deposits due to lack of oil changes o
r
improper oil viscosity can trigger actual vehicle faults
that were not previously monitored prior to OBD. Poo
r
vehicle maintenance can not be classified as a
“non-vehicle fault", but with the sensitivity of OBD
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.
Related System Faults
Many of the OBD system diagnostics will not run if the
ECM detects a fault on a related system or component.
One example would be that if the ECM detected a
Misfire fault, the diagnostics on the catalytic converte
r
would be suspended until 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 faul
t
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.
Maintenance Schedule
Refer to the Maintenance Schedule.
Visual/Physical Engine Compartment
Inspection
Perform a careful visual and physical engine
compartment inspection when performing any
diagnostic procedure or diagnosing the cause of an
emission test failure. This can often lead to repairing a
problem without further steps. Use the following
guidelines when performing a visual/physical inspection:
Inspect all vacuum hoses for punches, cuts,
disconnects, and correct routing.
Inspect hoses that are difficult to see behind othe
r
components.
Inspect all wires in the engine compartment fo
r
proper connections, burned or chafed spots, pinched
wires, contact with sharp edges or contact with ho
t
exhaust manifolds or pipes.
ENGINE LUBRICATION (6VE1 3.5L) 6G-7
Oil Pan and Crankcase
Removal
1. Disconnect battery ground cable.
2. Drain engine oil.
3. Lift vehicle by supporting the frame.
4. Remove front wheels.
5. Remove oil level dipstick from level gauge tube.
6. Remove stone guard.
7. Remove radiator under fan shroud.
NOTE: For 4WD model, remove front axle housing
assembly from chassis (steps 8 to 10).
8. Remove suspension cross member fixing bolts, 2
pcs each per side and remove suspension cross
member.
9. Remove pitman arm and relay lever assembly,
using the 5–8840–2005–0 remover, remove pitman
arm from the steering unit and remove four fixing
bolts for relay lever assembly.
10. Remove axle housing assembly four fixing bolts
from housing isolator side and mounting bolts from
wheel side. At this time support the axle with a
garage jack and remove axle housing assembly.
11. Remove oil pan fixing bolts.
12. Remove oil pan, using 5–8840–2153–0 seale
r
cutter, remove oil pan.
013RS003
13. Remove crankcase fixing bolts.
14. Remove crankcase, using 5–8840–2153–0 seale
r
cutter, remove crankcase.
NOTE: Do not deform or damage the flange of oil pan
and crankcase.
Replace the oil pan and/or crankcase if deformed o
r
damaged.
013RS003
Installation
1. Install crankcase.
1. Remove residual sealant, lubricant and moisture
from mounting surface, then dry thoroughly.
2. Properly apply a 4.5 mm (0.7 in) wide bead o
f
sealant (TB-1207C or equivalent) to mounting
surface of crankcase.
Sealant beat must be continuous.
The crankcase must be installed within 5
minutes after sealant application before the
sealant hardens.
013RW010
6G-8 ENGINE LUBRICATION (6VE1 3.5L)
3. Install crankcase, tighten crankcase fixing bolts
to the specified torque.
Torque : 10 N
m (1.0 kg
m/89 lb in)
013RW004
2. Install oil pan
1. Remove residual sealant, lubricant and moisture
from mounting surface, then dry thoroughly.
2. Properly apply a 4.5 mm (0.17 in) wide bead o
f
sealant (TB-1207C or equivalent) to mounting
surface of oil pan.
Sealant beat must be continuous.
The crankcase must be installed within 5
minutes after sealant application before the
sealant hardens.
013RW003
3. Install oil pan, tighten oil pan fixing bolts to the
specified torque.
Torque : 25 N
m (2.5 kg
m/18 lb ft)
3. Install axle housing assembly and tighten fixing
bolts to the specified torque (4WD model).
Axle case bolts
Torque : 116 N
m (11.8 kg
m/85 lb ft)
Mounting bolts
Torque : 168 N
m (17.2 kg
m/124 lb ft)
RTW34CSH000101
4. Install relay lever assembly and tighten fixing bolts.
Torque: 44 N
m (4.5 kg
m/32 lb ft)
5. Engage teeth of pitman arm and steering unit, and
tighten nut to the specified torque.
Torque : 216 N
m (22.0 kg
m/159 lb ft)
6. Install suspension cross member and tighten fixing
bolts to the specified torque.
Torque : 78 N
m (8.0 kg
m/58 lb ft)
7. Install radiator under fan shroud.
8. Install stone guard.
9. Install engine oil level dipstick.
10. Fill engine oil until full level on engine oil gauge
dipstick.
6G-10 ENGINE LUBRICATION (6VE1 3.5L)
Tighten fixing bolts to the specified torque.
Torque : 25 N
m (2.5 kg
m/18 lb ft)
051RW001
2. Install oil pipe with O-ring, tighten fixing bolt to the
specified torque.
Torque : 10 N
m (1.0 kg
m/7 lb ft)
3. Install oil strainer with O-ring, tighten fixing bolt to
the specified torque.
Torque : 25 N
m (2.5 kg
m/18 lb ft)
4. Install oil filter assembly and tighten bolts to the
specified torque.
Torque : 25 N
m (2.5 kg
m/18 lb ft)
050RW001
Legend
(1) Oil Pump
(2) Oil Filter
(3) Oil Gallery
(4) From Oil Filter
(5) To Oil Filter
5. Install timing pulley on crankshaft.
Install timing belt.
Refer to installation procedure for Timing Belt in
this manual.
6. Install crankshaft pulley.
Refer to install procedure for Crankshaft Pulley
in this manual.
7. Install crankcase assembly.
Refer to installation procedure for Oil Pan and
Crankcase in this manual.
8. Refill engine oil until full level on engine oil dipstick.
ENGINE LUBRICATION (6VE1 3.5L) 6G-11
Oil Pump Oil Seal
Removal
1. Disconnect battery ground cable.
2. Drain engine oil.
3. Remove crankshaft pulley.
Refer to removal procedure for Crankshaf
t
Pulley in this manual.
4. Remove timing belt.
Refer to removal procedure for Timing Belt in
this manual.
5. Remove timing pulley from crankshaft.
6. Remove oil pump oil seal using a sealer puller.
NOTE: Take care not to damage sealing surfaces of oil
pump and crankshaft when removing oil seal.
Installation
1. Install oil pump oil seal, apply engine oil to oil seal
lip, then install oil seal using 5–8840–2287–0
installer.
015RS001
2. Install timing pulley to crankshaft.
3. Install timing belt.
Refer to installation procedure for Timing Belt in
this manual.
4. Install crankshaft pulley.
Refer to installation procedure for Crankshaf
t
Pulley in this manual.
5. Refill engine oil until full level.
ENGINE DIAGNOSIS (C24SE) 6-3
3.Trouble in Fuel System
Condition Possible cause Correction
Starting motor turns over and
spark occurs but engine does not
start. Fuel tank empty Fill
Water in fuel system Clean
Fuel filter clogged Replace filter
Fuel pipe clogged Clean or replace
Fuel pump defective Replace
Fuel pump circuit open Correct or replace
Evaporative Emission Control
system circuit clogged Correct or replace
Multiport Fuel Injection System
faulty Refer to "Electronic Fuel Injection"
section
4.Engine Lacks Compression
Condition Possible cause Correction
Engine lacks compression Spark plug loosely fitted or spark
plug gasket defective Tighten to specified torque or
replace gasket
Spark plug wire incorrect Connect properly or replace
Valve timing incorrect Adjust
Cylinder head gasket defective Replace gasket
Valve incorrectly seated Lap valve
Valve stem seized Replace valve and valve guide
Valve spring weakened Replace
Cylinder or piston rings worn Overhaul engine
Piston ring seized Overhaul engine.
Engine Compression Test Procedure
1. Start and run the engine until the engine
reaches normal operating temperature.
2. Turn the engine off.
3. Remove all the spark plugs.
4. Remove ignition coil fuse (15A) and disable the
ignition system.
5. Remove the fuel pump relay from the relay and
fuse box. 6. Engage the starter and check that the cranking
speed is approximately 300 rpm.
7. Install cylinder compression gauge into spark
plug hole.
8. With the throttle valve opened fully, keep the
starter engaged until the compression gauge
needle reaches the maximum level. Note the
reading.
9. Repeat the test with each cylinder.
The pressure difference between the individual
cylinders should not exceed 100kPa (14.5 psi).
6-8 ENGINE DIAGNOSIS (C24SE)
Condition Possible cause Correction
Engine overheating Level of Engine Coolant too low Replenish
Thermo switch or fan motor
defective Replace
Thermostat defective Replace
Engine Coolant pump defective Correct or replace
Radiator clogged Clean or replace
Radiator filter cap defective Replace
Level of oil in engine crankcase
too low or wrong oil in engine Change or replenish
Resistance in exhaust system
increased Clean exhaust system or replace
defective parts
Throttle Position Sensor
adjustment incorrect Adjust Wide Open Throttle switch
setting
Throttle Position Sensor circuit
open or shorted Correct or replace
Cylinder head gasket damaged Replace
Cooling Fan clutch defective Replace
Fan belt slipping Adjust tension of V-belt or replace
V-belt
Engine overcooling Thermostat defective Replace (Use a thermostat set to
open at 92C (197.6F))
Engine lacks compression - Refer to Hard Start
Others Tire inflation pressure abnormal Adjust to recommend pressures
Brake drag Adjust
Clutch slipping Adjust or replace
Level of oil in engine crankcase
too high Correct level of engine oil
Engine Noisy
Abnormal engine noise often consists of various
noises originating in rotating parts, sliding parts and
other moving parts of the engine. It is, therefore,
advisable to locate the source of noise systematically.
Condition Possible cause Correction
Noise from crank journals or from
crank bearings
(Faulty crank journals and crank
bearings usually make dull noise
that becomes more evident when
accelerating) Oil clearance increased due to
worn crank journals or crank
bearings Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing
Crankshaft out of round Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing
Crank bearing seized Replace crank bearings and
crankshaft or regrind crankshaft
and install the over size bearing
ENGINE DIAGNOSIS (C24SE) 6-13
Fuel Consumption Excessive
Condition Possible cause Correction
Trouble in fuel system Mixture too rich or too lean due to
trouble in fuel injection system Refer to "Abnormal Combustion"
Fuel cut function does not act Refer to "Abnormal Combustion"
Trouble in ignition system Misfiring or abnormal combustion
due to trouble in ignition system Refer to Hard Start or Abnormal
Combustion Troubleshooting
Guide
Others Engine idle speed too high Reset Idle Air Control Valve
Returning of accelerator control
sluggish Correct
Fuel system leakage Correct or replace
Clutch slipping Correct
Brake drag Correct
Selection of transmission gear
incorrect Caution operator of incorrect gear
selection
Oil Problems
Condition Possible cause Correction
Oil pressure too low Wrong oil in use Replace with correct engine oil
Relief valve sticking Replace
Oil pump not operating properly Correct or replace
Oil pump strainer clogged Clean or replace strainer
Oil pump worn Replace
Oil pressure gauge defective Correct or replace
Crankshaft bearing or connecting
rod bearing worn Replace
Oil contamination Wrong oil in use Replace with new engine oil
Oil filter clogged Replace oil filter
Cylinder head gasket damage Replace gasket
Burned gases leaking Replace piston and piston rings or
rebore cylinders
Oil not reaching valve system Oil passage in cylinder head or
cylinder body clogged Clean or correct
Engine Oil Pressure Check
1. Check for dirt, gasoline or water in the engine
oil.
a. Check the viscosity of the oil.
b. Change the oil if the viscosity is outside the
specified standard.
c. Refer to the "Maintenance and Lubrication"
section of this manual.
2. Check the engine oil level.
The level should fall somewhere between the
"ADD" and the "FULL" marks on the oil level
dipstick.
If the oil level does not reach the "ADD" mark on
the oil level dipstick, engine oil must be added. 3. Remove the oil pressure unit.
4. Install an oil pressure gauge.
5. Start the engine and allow the engine to reach
normal operating temperature (About 80C).
6. Measure the oil pressure.
Oil pressure should be:
150 kPa(21.8 psi) at idle speed.
7. Stop the engine.
8. Remove the oil pressure gauge
9. Install the oil pressure unit.
10. Start the engine and check for leaks.