Cylinder Leakage Test
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
- When a cylinder produces a low reading, use of a cylinder leakage tester will be helpful in pinpointing the exact cause.
- The cylinder leakage tester is connected to the Compression Tester Adaptor, the piston is brought up to TDC on the compression stroke, and compressed air is admitted.
- Once the combustion chamber is pressurized, the leakage tester gauge will read the percentage of leakage. Leakage exceeding 20% is excessive.
- While the air pressure is retained in the cylinder, listen for the hiss of escaping air. A leak at the intake valve will be heard in the TB (throttle body). A leak at the exhaust valve can be heard at the tailpipe. Leakage past the piston rings will be audible at the crankcase vent oil separator connection. If air is passing through a blown head gasket to an adjacent cylinder, the noise will be evident at the spark plug hole of the cylinder into which the air is leaking. Cracks in the cylinder block or gasket leakage into the cooling system may be detected by a stream of bubbles in the radiator.
- Install the fuel injectors.For additional information, refer to: Fuel Injectors LH . and For additional information, refer to: Fuel Injectors RH .