Compression - Metro

Warm engine to normal operating temperature before checking the compression. Ensure battery is fully charged. Disconnect electrical connector(s) at ignition coil(s). Remove main relay from relay box. Relay box is located on left side of engine compartment, behind battery. Check engine mechanical condition with a compression gauge, vacuum gauge, or engine analyzer with throttle fully open. See engine analyzer manual for specific instructions. See COMPRESSION SPECIFICATIONS  table. Install and tighten spark plugs to 21 ft. lbs. (28 N.m).