Piston rings maintain combustion pressure in the cylinder and prevent oil from seeping into the combustion chamber.
Ring failure results in
- white exhaust smoke
- excessive oil consumption
- compromised performance
To verify the need for piston ring maintenance, the technician uses a compression tester to check for low compression readings. The technician may also refine the check by squirting some medium-weight oil into each plug hole, cranking the engine, and repeating the compression test.
If the readings are significantly higher, there is a problem with the rings or cylinder. If no changes are evident, the trouble is with the valves.
A significant drop in pressure in one or more cylinders can be indicative of several problems, including a blown head gasket.
TIP: A broken compression ring may produce a misfire in the affected cylinder.
Don't miss a weekly "You Auto Know" automotive tip. CLICK HERE to sign up. Please drive safely.
Have vehicle concerns? CLICK HERE for our FREE CHECKLIST 5 Common Transmission Concern MISTAKES before you contact a repair shop.