Measure the outside diameter [D] of the seating pattern on the valve seat.
If the outside diameter is too large or too small, repair the seat (see Valve Seat Repair).
Valve Seating Surface Outside Diameter Standard:
Exhaust 23.9 
24.1 mm (0.941
0.949 in.)
Intake 30.4 
30.6 mm (1.197
1.205 in.)
Measure the seat width [E] of the portion where there is no build-up carbon (white portion) of the valve seat with a vernier caliper.
Good [F]
If the width is too wide [G], too narrow [H] or uneven [J], repair the seat (see Valve Seat Repair).
Valve Seating Surface Width Standard:
Exhaust 0.8 
1.2 mm (0.03
0.05 in.)
Intake 0.5 
1.0 mm (0.02
0.04 in.)
Valve-to-Guide Clearance Measurement (Wobble Method)
Valve Seat RepairECU Communication Error (Service Code 39)
ECU Communication Line Inspection
When the data is not sent from the ECU to the meter unit
for more than about 10 seconds, the service code 39 is
displayed.
The data is sent through the CAN communication line.
The service code 39 is detected with the meter unit.
When the user mode, this commun ...
Valve Clearance
Valve and valve seat wear decreases
valve clearance, upsetting valve timing.
NOTICE
If valve clearance is left unadjusted,
wear will eventually
cause the valves to remain
partly open; which lowers performance,
burns the valves and
valve seats, and may cause serious
engine damage.
Valve cle ...
Shift Fork Guide Pin/Drum Groove Wear Inspection
Measure the diameter of each shift fork guide pin [A], and
measure the width [B] of each shift drum groove.
If the guide pin on any shift fork is less than the service
limit, the fork must be replaced.
Shift Fork Guide Pin Diameter
Standard: 6.9 7.0 mm (0.272
0.276 in.)
Service Limit: ...