Compression (Celica, Corolla & Matrix)
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 2003 Toyota Tacoma, 2003 Toyota RAV4, 2003 Toyota Prius, 2003 Toyota Matrix, and 2003 Toyota MR2. However, it is still accessible from the selected car via links, so may be relevant.
- Warm engine to normal operating temperature before checking the compression. Shut engine off. Ensure battery is fully charged.
- Disconnect electrical connectors at ignition coils. Remove ignition coils and spark plugs.
- Check compression by inserting a compression gauge into the spark plug hole. Fully open the throttle. While cranking the engine, read compression in a short a time as possible. Ensure compression is within specification. See COMPRESSION SPECIFICATIONS table.
- If the cylinder compression is low, pour a small amount of engine oil into the cylinder through the spark plug hole and inspect again. If adding oil increases the compression, it is likely that the piston rings and/or cylinder bore are worn or damaged. If pressure stays low, a valve may be sticking or seating improperly, or there may be leakage past the gasket.
- On Celica, install and tighten spark plugs to 13 ft. lbs. (18 N.m) and ignition coil retaining bolts to 80 INCH lbs. (9.0 N.m). On Corolla and Matrix, install and tighten spark plugs to 18 ft. lbs. (25 N.m) and ignition coil retaining bolts to 80 INCH lbs. (9.0 N.m).