ENGINE MECHANICAL (6VE1 3.5L) 6A-5
3. Trouble In Fuel System
Symptom Possible Cause Action
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 faultyRefer to “Electronic Fuel Injection"
section
4. Engine Lacks Compression
Symptom Possible Cause Action
Engine lacks compression Spark plug loosely fitted Tighten to specified torque
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 or broken 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 gage needle
reaches the maximum level. Note the reading.
9. Repeat the test with each cylinder.
If the compression pressure obtained falls belo
w
the limit, engine overhaul is necessary.
Limit; 1000 kPa (145 psi)
6A-6 ENGINE MECHANICAL (6VE1 3.5L)
Rough Engine Idling or Engine Stalling
Symptom Possible Cause Action
Trouble in fuel injection system Idle air control valve defective Replace
Throttle shutting off incomplete Replace
Throttle position sensor circuit open
or shorted Correct or replace
Fuel injector circuits open or shortedCorrect or replace
Fuel injectors damaged Replace
Fuel pump relay defective Replace
Mass Airflow Sensor circuit open or
poor connections Correct or replace
Mass Airflow Sensor defective Replace
Engine Coolant Temperature Sensor
circuit open or poor connections Correct or replace
Engine Coolant Temperature Sensor
defective Replace
Intake Air Temperature sensor circuit
open or poor connections Correct or replace
Intake Air Temperature sensor
defective Replace
Vehicle Speed Sensor circuit open or
shorted Correct or replace
Vehicle Speed Sensor defective Replace
Trouble in emission control system EGR valve defective Replace
EGR valve circuit open or poor
connection Correct or replace
Engine Control Module defective Replace
Canister purge valve circuit open or
poor connections Correct or replace
Canister purge valve defective Replace
Evaporative Emission Canister Purge
control valve defective Replace
Trouble in ignition system Refer to “Hard Start"
Others Engine lacks compression Refer to “Hard Start"
Valve incorrectly seated Lap valve
Air Cleaner Filter clogged Replace filter element
Valve timing incorrect Readjust
Idle air control valve broken Replace
Fast idle solenoid defective Replace
Positive Crankcase Ventilation valve
defective or clogged Replace
6A-8 ENGINE MECHANICAL (6VE1 3.5L)
Hesitation
Symptom Possible Cause Action
Hesitation on acceleration Throttle Position Sensor adjustment
incorrect Replace throttle valve assembly
Throttle Position Sensor circuit open
or shorted Correct or replace
Excessive play in accelerator linkageAdjust or replace
Mass Airflow Sensor circuit open or
poor connections Correct or replace
Mass Airflow Sensor defective Replace
Intake Air Temperature (IAT) Sensor
circuit open or poor connections Correct or replace
IAT Sensor defective Replace
Hesitation at high speeds
(Fuel pressure too low) Fuel tank strainer clogged Clean or replace
Fuel pipe clogged Clean or replace
Fuel filter clogged Replace
Defective fuel pump system Check and replace
Fuel Pressure Control Valve leaking Replace
Hesitation at high speeds
(Fuel injector not working normally) Power supply or ground circuit for
Multiport Fuel Injection System
shorted or open Check and correct or replace
Fuel Injector defective Replace
Cable of Multiport Fuel Injection
System circuit open or poor
connections Correct or replace
6A-10 ENGINE MECHANICAL (6VE1 3.5L)
Engine Lacks Power
Symptom Possible Cause Action
Trouble in fuel system Fuel Pressure Control Valve not
working normally Replace
Fuel injector clogged Clean or replace
Fuel pipe clogged Clean
Fuel filter clogged or fouled Replace
Fuel pump drive circuit not working
normally Correct or replace
Fuel tank not sufficiently breathing
due to clogged Evaporative Emission
Control System circuit Clean or replace
Water in fuel system Clean
Inferior quality fuel in fuel system Use fuel of specified octane rating
Engine Control Module supplied poor
voltage Correct circuit
Throttle Position Sensor cable broken
or poor connections Correct or replace
Throttle Position Sensor defective Replace
Mass Airflow Sensor not working
normally Replace
Manifold Absolute Pressure Sensor
not working normally Replace
Intake Air Temperature Sensor not
working normally Replace
Engine Coolant Temperature Sensor
circuit open or shorted Correct or replace
Engine Coolant Temperature Sensor
defective Replace
Engine Control Module defective Replace
Trouble in intake or exhaust system Air Cleaner Filter clogged Replace filter element
Air duct kinked or flattened Correct or replace
Exhaust system clogged Correct or replace
Ignition failure ———— Refer to Hard Start Troubleshooting
Guide
Heat range of spark plug inadequateInstall spark plugs of adequate heat
range
Ignition coil defective Replace
ENGINE MECHANICAL (6VE1 3.5L) 6A-15
Abnormal Combustion
Symptom Possible Cause Action
Trouble in fuel system Fuel pressure control valve defectiveReplace
Fuel filter clogged Replace
Fuel pump clogged Clean or replace
Fuel tank or fuel pipe clogged Clean or replace
Fuel injector clogged Clean or replace
Fuel pump relay defective Replace
Power supply cable for fuel pump
broken or poor connections Reconnect, correct or replace
Mass Airflow (MAF) Sensor circuit
open or defective Correct or replace
MAF Sensor defective Replace
Engine Coolant Temperature (ECT)
Sensor circuit open or shorted Correct or replace
ECT Sensor defective Replace
Throttle Position Sensor adjustment
incorrect Readjust
Throttle Position Sensor defective Replace
Throttle Position Sensor connector
poor connections Reconnect
Vehicle Speed Sensor cable poor
connections or defective Correct or replace
Vehicle Speed Sensor loosely fixed Fix tightly
Vehicle Speed Sensor in wrong
contact or defective Replace
Engine Control Module cable poor
connections or defective Correct or replace
6A-18 ENGINE MECHANICAL (6VE1 3.5L)
Fuel Consumption Excessive
Symptom Possible Cause Action
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 work 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"
Others Engine idle speed too high Reset to Section 6E
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
Lubrication Problems
Symptom Possible Cause Action
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 correct engine oil
Oil filter clogged Replace oil filter
Cylinder head gasket damage Replace gasket
Burned gases leaking Replace piston and piston rings or
cylinder body assembly
Oil not reaching valve system Oil passage in cylinder head or
cylinder body clogged Clean or correct
ENGINE FUEL (6VE1 3.5L) 6C-1
ENGINE
ENGINE FUEL (6VE1 3.5L)
CONTENTS
Service Precaution................................................. 6C-1
General Description............................................... 6C-2
Fuel Metering.......................................................... 6C-3
Fuel Filter................................................................. 6C-4
Removal............................................................... 6C-4
Inspection............................................................. 6C-4
Installation............................................................ 6C-4
Inspection............................................................. 6C-4
In-Tank Fuel Filter............................................... 6C-4
Fuel Pump Flow Test......................................... 6C-4
Fuel Pump............................................................... 6C-6
Fuel Pump and Associated Parts..................... 6C-6
Removal............................................................... 6C-6
Installation............................................................ 6C-7
Fuel Tube / Quick - Connector Fittings............... 6C-8
Precautions.......................................................... 6C-8
Cautions During Work........................................ 6C-8
Removal................................................................ 6C-8
Reuse of Quick-Connector................................. 6C-9
Assembling Advice.............................................. 6C-9
Fuel Pump Relay..................................................... 6C-10
General Description............................................ 6C-10
Fuel Tank................................................................. 6C-11
Fuel Tank and Associated Parts....................... 6C-11
Removal................................................................ 6C-11
Installation............................................................. 6C-12
Filler Neck................................................................ 6C-13
Removal................................................................ 6C-13
Installation............................................................. 6C-13
Fuel Gauge Unit...................................................... 6C-13
Removal and Installation.................................... 6C-13
Fuel Filler Cap......................................................... 6C-14
General Description............................................ 6C-14
Inspection............................................................. 6C-14
Main Data and Specifications................................ 6C-15
Special Tool.......................................................... 6C-16
Service Precaution
When working on the fuel system, there are several
things to keep in mind:
Any time the fuel system is being worked on,
disconnect the negative battery cable except
for those tests where battery voltage is
required.
Always keep a dry chemical (Class B) fire
extinguisher near the work area.
Replace all pipes with the same pipe and
fittings that were removed.
Clean and inspect “O" rings. Replace i
f
required.
Always relieve the line pressure before
servicing any fuel system components.
Do not attempt repairs on the fuel system until
you have read the instructions and checked
the pictures relating to that repair.
Adhere to all Notices and Cautions.
All gasoline engines are designed to use only
unleaded gasoline. Unleaded gasoline must be
used for proper emission control system operation.
Its use will also minimize spark plug fouling and
extend engine oil life. Using leaded gasoline can
damage the emission control system and could
result in loss of emission warranty coverage.
All cars are equipped with an Evaporative Emission
Control System. The purpose of the system is to
minimize the escape of fuel vapors to the
atmosphere.
6C-2 ENGINE FUEL (6VE1 3.5L)
General Description
RTW36CLF000301
Legend (8) Fuel Rail Left
(1) Fuel Filler Cap (9) Intake Air Port Left Bank
(2) Fuel Tank (10) Fuel Pressure Control Valve
(3) Rollover Valve (11) Common Chamber
(4) Fuel Pump and Sender Assembly (12) Duty Solenoid Valve
(5) Fuel Filter (13) Throttle Valve
(6) Fuel Rail Right (14) Canister
(7) Intake Air Port Right Bank (15) Evapo Control Valve