M.I.L. ªONº 1MZ±FE ENGINE MISFIRE DTC P0300 ± P0306 ± EG008-04April 28, 2004
Page 2 of 3
PREVIOUS PART NUMBERCURRENT PART NUMBERPART NAMEQTY
90080±19012SameIgnition Coil Assembly1
SPECIAL SERVICE TOOLS (SSTs)PART NUMBERQUANTITY
Toyota Diagnostic Tester Kit*
010012711
12 Megabyte Diagnostic Tester Program Card
with version 10.2a Software (or later)*01002593-0051
* Essential SSTs.
NOTE:
Additional Diagnostic Tester Kits, Program Cards or other SSTs may be ordered by
calling SPX/OTC at 1-800-933-8335.
TOOLS & MATERIALQUANTITY
Digital Volt Ohmmeter (DVOM)1
1. Confirm if vehicle is currently misfiring, running rough or hesitating.
If YES ± Go to Step 2.
If NO ± Review Freeze Frame Data and attempt to operate vehicle under similar
driving conditions ± see notes below for information that makes it more likely to
duplicate misfire.
NOTE:
The following activities will turn off misfire detection:
Changing engine RPM greater than 150 RPM.
Changing throttle position quickly.
Misfire duplication can be duplicated most readily when the engine speed and throttle
angle are held nearly constant for at least 2 minutes.
A
IGNITION 41
CYL #1 0%
CYL #2 0%
CYL #3 0%
CYL #4 Above 50%
CYL #5 0%
CYL #6 0%
MISFIRE RPM 0rpm
MISFIRE LOAD 0.00g/rev
# CODES 1
CHECK MODE OFF
MISFIRE TEST COMPL
B
IGNITION 205
CYL #1 0%
CYL #2 0%
CYL #3 0%
CYL #4 Above 50%
CYL #5 0%
CYL #6 0%
MISFIRE RPM 0rpm
MISFIRE LOAD 0.00g/rev
# CODES 1
CHECK MODE OFF
MISFIRE TEST COMPL
NOTE:
When misfire monitor is active, ignition value will change on Data List.
When pending misfire DTC is set, ªMISFIRE RPMº and ªMISFIRE LOADº will show values.
Values Will Change
From Zero
Parts
Information
Required
SSTs
Required
Tools &
Material
Repair
Procedure
M.I.L. ªONº 1MZ±FE ENGINE MISFIRE DTC P0300 ± P0306 ± EG008-04April 28, 2004
Page 3 of 3
2. Confirm if misfire is currently occurring on cylinder(s) identified by DTC(s) using the
Diagnostic Tester while engine is idling (see below).
FUNCTION SELECT FOR
NORTH AMERICA
B A
DIAGNOSTIC MENU
ENGINE
C
ALL
USER DATA
EXTEND DATA
AT M
02 SENSOR
FUEL SYS
CATALYTIC
EVAP
E
SELECT DATA
D
MISFIRE
1: OBD/MOBD
3: CARB OBD II
4: BREAK±OUT BOX
5: NVH
6: AUTOPROBE
7: 02 RPM CHECK
8: SNAPSHOT REVIEW
9: SETUP
0: GAS ANALYSIS2: ENHANCED OBD
2: DTC INFO
3: ACTIVE TEST
4: SNAPSHOT
5: SYSTEM CHECK
6: RESET MEMORY
7: MONITOR STATUS
8: CHECK MODE1: DATA LIST Examining Data List For Misfire Percent
NOTICE
ENHANCED OBDII
COVERS VEHICLES
THROUGH 2004MY.
EXCEPT SEQUOIA,
TUNDRA, TACOMA.
FOR OTHER VEHICLES
SELECT 2004 NEW
MODEL OR USE CARB
OBDII
PRESS [ENTER]
IGNITION 41
CYL #1 0%
CYL #2 0%
CYL #3 0%
CYL #4 Above 50%
CYL #5 0%
CYL #6 0%
MISFIRE RPM 0rpm
MISFIRE LOAD 0.00g/rev
# CODES 1
CHECK MODE OFF
MISFIRE TEST COMPL
Misfire on #4 Cylinder
Is the cylinder(s) identified by the DTC(s) misfiring?
If YES ± Go to Step 3.
If NO ± Follow normal diagnostics for applicable DTC in Technical Information System
(TIS) in applicable Repair Manual:
Diagnostics: SFI: P030#.
3. Swap suspect ignition coil(s) from cylinder that is misfiring to cylinder that is
not misfiring.
4. Using Diagnostic Tester, confirm that misfire is now occurring in cylinder that has
suspect ignition coil(s). Has misfire followed swapped ignition coil(s)?
If YES ± Replace ignition coil(s) and go to Step 5.
If NO ± Follow normal diagnostics in Technical Information System (TIS) for
applicable Repair Manual:
Diagnostics: SFI: P030#.
5. Confirm misfire has been eliminated (0% at all times) using Diagnostic Tester while
engine is idling.
NOTE:
If misfire percent is any value other than 0% at any time, then that cylinder is misfiring. Repair
Procedure
(Continued)
