Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Toyota >> 2003 >> Matrix Base, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures - 4-Cylinder >> Preliminary Inspection & Adjustments >> Mechanical Inspection >> Compression (MR2)

Compression (MR2)

  1. Warm engine to normal operating temperature before checking the compression. Shut engine off. Ensure battery is fully charged.
  2. Disconnect electrical connectors at ignition coils. Remove ignition coils and spark plugs.
  3. Check compression by inserting a compression gauge into the spark plug hole. Fully open the throttle. Read compression in a short a time as possible. Ensure compression is within specification. See COMPRESSION SPECIFICATIONS  table.
  4. 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.
  5. Install and tighten spark plugs to 19 ft. lbs. (26 N.m) and ignition coil retaining bolts to 80 INCH lbs. (9.0 N.m).
scientia non olet · About Mike's Workshop Manuals