Adjust the engine idle speed periodically on the engine at normal operating temperature.
To adjust the idle speed:

Engine oil and filter change
Throtile cable playGearshift linkage inspection
Refer to “gearshift shaft / gearshift cam plate removal and installation” .
Gearshift shaft
Check the gearshift shaft for bend or wear.
Check the return spring for damage or fatigue.
If any defects are found, replace the defective part(-s).
Gearshift shaft oil seal
Inspect the gearshif ...
Air cleaner element inspection
Inspect air cleaner element
every 6 000 km (4 000 miles, 12 months)
Inspection
Remove the air cleaner element. Refer to “air cleaner element removal
and installation” in section 1d .
Inspect the air cleaner element for clogging. If it is
clogged with dirt, replace it with a new on ...
DTC “c21” (p0110-h/l): iat sensor circuit
malfunction
Detected condition and possible cause
Detected condition
Possible cause
C21
Output voltage is not with in the following
range.
0.15 V ≤ Sensor voltage < 4.85 V
Iat sensor circuit open or short.
Iat sensor malfunction.
Ec ...