
13-1
GROUP 13
FUEL
CONTENTS
MULTIPORT FUEL INJECTION (MFI) <2.4 L ENGINE> . . . . . . 13A
MULTIPORT FUEL INJECTION (MFI) <3.0 L ENGINE> . . . . . . 13B
FUEL SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13C
13A-2
GROUP 13A
MULTIPORT FUEL
INJECTION (MFI)
<2.4L ENGINE>
CONTENTS
GENERAL DESCRIPTION. . . . . . . . . 13A-3 FUEL PUMP CONNECTOR DISCONNECTION
(HOW TO REDUCE PRESSURIZED FUEL LINES)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13A-478
MULTIPORT FUEL INJECTION (MFI)
FUEL PUMP OPERATION CHECK . . . . . . 13A-478
DIAGNOSIS . . . . . . . . . . . . . . . . . . . . 13A-5
MULTIPORT FUEL INJECTION (MFI) RELAY
TROUBLESHOOTING STRATEGY . . . . . . 13A-5
AND FUEL PUMP RELAY CONTINUITY
TROUBLE CODE DIAGNOSIS. . . . . . . . . . 13A-5 CHECK . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13A-479
FAIL-SAFE/BACKUP FUNCTION TABLE . 13A-19 INTAKE AIR TEMPERATURE SENSOR
DIAGNOSTIC TROUBLE CODE CHART . . 13A-20 CHECK . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13A-479
SYMPTOM CHART. . . . . . . . . . . . . . . . . . . 13A-22 ENGINE COOLANT TEMPERATURE
DIAGNOSTIC TROUBLE CODE SENSOR CHECK . . . . . . . . . . . . . . . . . . . . 13A-479
PROCEDURES. . . . . . . . . . . . . . . . . . . . . . 13A-26 THROTTLE POSITION SENSOR CHECK . 13A-480
SYMPTOM PROCEDURES . . . . . . . . . . . . 13A-339 HEATED OXYGEN SENSOR CHECK . . . . 13A-481
DATA LIST REFERENCE TABLE . . . . . . . 13A-442 INJECTOR CHECK . . . . . . . . . . . . . . . . . . . 13A-483
ACTUATOR TEST REFERENCE TABLE. . 13A-450 IDLE AIR CONTROL MOTOR
CHECK AT THE ENGINE CONTROL MODULE (STEPPER MOTOR) CHECK . . . . . . . . . . . 13A-483
(ECM) OR POWERTRAIN CONTROL EVAPORATIVE EMISSION PURGE
MODULE (PCM) . . . . . . . . . . . . . . . . 13A-452 SOLENOID CHECK . . . . . . . . . . . . . . . . . . 13A-485
INSPECTION PROCEDURE USING AN EGR SOLENOID CHECK . . . . . . . . . . . . . . 13A-485
OSCILLOSCOPE . . . . . . . . . . . . . . . . . . . . 13A-457
INJECTOR . . . . . . . . . . . . . . . . . . . . . 13A-486
SPECIAL TOOLS. . . . . . . . . . . . . . . . 13A-467 REMOVAL AND INSTALLATION . . . . . . . . 13A-486
ON-VEHICLE SERVICE. . . . . . . . . . . 13A-468 THROTTLE BODY ASSEMBLY . . . . . 13A-488
COMPONENT LOCATION . . . . . . . . . . . . . 13A-468 REMOVAL AND INSTALLATION . . . . . . . . 13A-488
THROTTLE BODY (THROTTLE VALVE AREA) DISASSEMBLY AND ASSEMBLY . . . . . . . 13A-489
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . 13A-472
THROTTLE POSITION SENSOR SPECIFICATIONS . . . . . . . . . . . . . . . 13A-492
ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . 13A-473
FASTENER TIGHTENING
BASIC IDLE SPEED ADJUSTMENT . . . . . 13A-474
SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . 13A-492
FUEL PRESSURE TEST . . . . . . . . . . . . . . 13A-475
GENERAL SPECIFICATIONS . . . . . . . . . . 13A-492
SERVICE SPECIFICATIONS . . . . . . . . . . . 13A-493
SEALANT . . . . . . . . . . . . . . . . . . . . . . . . . . 13A-493
MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE> 13A-3
GENERAL DESCRIPTION
.
G EN ER AL DESC RIPTIO N
M1131000100154
The Multiport Fuel Injection System consists of control (IAC) motor according to engine coolant
sensors, actuators and the engine control module temperature, A/C, and other electrical load. Thus,
(ECM) or powertrain control module (PCM) idle speed is kept at an optimum speed. In addition,
. The sensors detect the engine condition. The when the air conditioning switch is turned off and on
module controls the system based on signals from while the engine is idling, the IAC motor adjusts the
these sensors. The actuators work under the control throttle valve bypass air amount. Thus, idle speed is
of the ECM or PCM . The ECM maintained at constant speed regardless of various
or PCM carries out activities such as fuel engine load conditions.
injection control, idle air control, and ignition timing
control. In addition, the ECM or PCM IGNITION TIMING CONTROL
has several diagnostic test modes which simplify The ignition power transistor located in the ignition
troubleshooting when a problem develops. In primary circuit turns on and off to control primary
addition, the ECM or PCM is equipped current flow to the ignition coil. This maintains
with several diagnostic test modes which simplify ignition timing at an optimum level regardless of
troubleshooting when a problem develops. various engine operating conditions. The ECM or PCM determines the ignition timing
FUEL INJECTION CONTROL according to engine speed, intake air volume, engine
The ECM or PCM controls injector coolant temperature, and atmospheric pressure.
drive times and injector timing to supply the optimum
air/fuel mixture to the engine according to the DIAGNOSTIC TEST MODE
continually-changing engine operation conditions. A