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 playWater pump removal and installation
Removal
Note
before draining engine oil and engine coolant, inspect engine oil and
coolant leakage between the water pump and crankcase. If engine oil is
leaking, visually inspect the oil seal and o-ring. If engine coolant is
leaking, visually inspect the mechanical seal and s ...
DTC “c31” (p0705): gp switch circuit
malfunction
Detected condition and possible cause
Detected condition
Possible cause
No gear position switch voltage
Gp switch voltage is not within the following range.
Gp switch voltage > 0.6 V
Gp switch circuit open or short.
Gp switch malfunction.
...
Exhaust control valve inspection
Inspect exhaust control valve
initially at 1 000 km (600 miles, 2 months) and every
12 000 km (7 500 miles, 24 months) thereafter
Inspect exhaust control valve as follows:
remove the left side cowling. Refer to “exterior parts removal and
installation” in section 9d .
Check t ...