Prizm L4-108 1.8L DOHC VIN 8 MFI (1998)
Compression Check: Testing and Inspection
Perform a compression test in order to determine the cylinder compression pressure. Use a compression test in order to diagnose lack of power,
excessive oil consumption, or poor fuel economy.
1. Verify that the battery is fully charged or close to fully charged.
NOTICE: This engine is equipped with an aluminum cylinder head. Allow the engine to cool before removing spark plugs. Removing the spark
plugs from an engine at operating temperature may damage the spark plug threads in the cylinder head. Also be sure to clean any dirt or debris
from around spark plug holes prior to removing spark plugs.
IMPORTANT: The engine should be at room temperature.
2. Remove the secondary (spark plug) wires from the spark plugs.
3. Remove the spark plugs from the cylinder head.
4. Disconnect the electrical connectors at both ignition coils (1,2).
5. Remove the EFI Main Relay (2) from the Fuse/Relay Block 1.
6. Install a compression gage into a spark plug hole.
