G420E/G424E
Tier
LP Engine
Table of Contents
5
Index
WORKING WITH LPG EQUIPMENT
CHAPTER 0 LPG AND LPG FUEL TANKS
LPG Fuel Supply........................................................ 8
LPG Fuel Tanks.......................................................... 9
Installing LPG Fuel Tanks .......................................... 9
LPG Fuel Tank Components .................................... 10
Fuel Gauge .............................................................. 10
Service Valve ........................................................... 10
Quick Disconnect Coupling...................................... 11
Filler Valve................................................................ 11
CHAPTER 1 ENGINE SPECIFICATION
Indication of Engine Serial Number.......................... 12
Specifications(G420E) ............................................. 13
Specifications(G424E) ............................................. 14
CHAPTER 2 MI-04 LPG SYSTEM
OPERATIONAL OVERVIEW
MI-04 General Description ....................................... 15
MI-04 LP Fuel Filter.................................................. 17
MI-04 Fuel Lock-Off (Electric) .................................. 17
MI-04 N-2001 Regulator/Converter.......................... 18
N-2001 Theory of Operation .................................... 19
MI-04 N-CA55-500TR Mixer .................................... 20
N-CA55-500-TR Air/Fuel Mixer Theory of
Operation ................................................................. 20
MI-04 Electronic Throttle .......................................... 22
MI-04 Fuel Trim Valve .............................................. 23
Heated Exhaust Gas Oxygen Sensor (HEGO) ........ 24
MI-04 SECM (General Description) ......................... 25
MI-04 SECM (Fuel Management) ............................ 25
MI-04 SECM (Load/Speed Management)................ 27
MI-04 Ignition management ..................................... 29
CHAPTER 3 MI- 04 MAINTENANCE
SCHEDULE
RECOMMENDED MAINTENANCE SCHEDULE.....30
Test Fuel System for Leaks ......................................30
Inspect Engine for Fluid Leaks .................................30
Inspect Vacuum Lines and Fittings...........................30
Inspect Electrical System .........................................30
Inspect Acceleration Pedal Operation ......................31
Check Coolant Level ................................................31
Inspect Coolant Hoses .............................................31
Inspect Battery System ............................................31
Inspect Ignition System ............................................31
Replace Spark Plugs ................................................31
Replace LP Fuel Filter Element................................32
Testing Fuel Lock-off Operation................................33
Pressure Regulator/Converter Testing and
nspection ..................................................................33
Fuel Trim Valve Inspection (FTV) .............................33
Inspect Air/Fuel Valve Mixer Assembly.....................33
Inspect for Intake Leaks ...........................................34
Inspect Throttle Assembly ........................................34
Checking the TMAP Sensor .....................................34
Inspect Engine for Exhaust Leaks............................34
Replace Oxygen Sensor ..........................................34
Maintenance Schedule.............................................35
CHAPTER 4 MI-04 LP BASIC
TROUBLESHOOTING
Basic Troubleshooting ..............................................37
CHAPTER 5 MI-04 LP ADVANCED
DIAGNOSTICS
Advanced Diagnostics..............................................44
Reading Diagnostic Fault Codes..............................44
Displaying Fault Codes (DFC) From SECM
Memory ....................................................................45
Clearing Fault (DFC) Codes.....................................45
Fault Action Descriptions..........................................45
Fault List Definitions .................................................46
Table a. MI-04 Diagnostic Fault Codes (Flash
Codes)......................................................................48
CHAPTER 6 MI-04 ELECTRICAL
CONNECTIONS
Resistance Checks...................................................62
Voltage Checks.........................................................63
