Open and support the front end of the fuel tank (page 3-4).
Disconnect the fuel pump 3P black connector.
Stop the engine, disconnect the spark plug caps and remove one spark plug at a time.
Shift the transmission into neutral.
Install the compression gauge into the spark plug hole.
Open the throttle all the way and crank the engine with the starter motor.
Crank the engine until the gauge reading stops rising. The maximum reading is usually reached within 4-7 seconds.
The cylinder compression pressure is low because each camshaft has a decompression device installed.
Compression pressure: 657 kPa (6.7 kgf/cm2, 95 psi) - at 320 rpm.
If the compression is high, it indicates that carbon deposits have accumulated on the combustion chamber and/or the piston crown.
If compression is low, pour 3-5 cc (0.1-0.2 oz) of clean engine oil into the cylinder through the spark plug hole and recheck the cylinder, piston and piston rings.
If compression is the same as the previous value, check the valves for leakage.