Compression Check: Testing and Inspection

Engine Compression Inspection

NOTE: After this inspection, you must reset the powertrain control module (PCM). Otherwise, the PCM will continue to stop the injectors from functioning.

1. Warm up the engine to normal operating temperature (cooling fan comes on).

2. Turn the ignition switch to LOCK (0).

3. Connect the HDS to the data link connector (DLC). Initial Inspection and Diagnostic Overview

4. Turn the ignition switch to ON (II).

5. Make sure the HDS communicate, with the vehicle and the PCM If it doesn't communicate, troubleshoot the DLC circuit.. Testing and Inspection

6. Select PGM-FI, INSPECTION, then ALL INJECTORS STOP on the HDS.

7. Turn the ignition switch to LOCK (0).

8. Remove the four ignition coils. Service and Repair

9. Remove the four spark plugs.

10. Attach the compression gauge to the spark plug hole.

11. Open the throttle fully, then crank the engine with the starter motor and measure the compression.

Compression Pressure:
Above 930 kPa (9.5 kgf/cm2, 135 psi)

12. Measure the compression on the remaining cylinders.

Maximum Variation:
Within 200 kPa (2.0 kgf/cm2, 28 psi)

13. If the compression is not within specifications, check the following items, then remeasure the compression.
- Damaged or worn valves and seats

- Damaged cylinder head gasket

- Damaged or worn piston rings

- Damaged or worn piston and cylinder bore

14. Remove the compression gauge from the spark plug hole.

15. Install the four spark plugs.

16. Install the four ignition coils Service and Repair .

17. Select the PCM reset Initial Inspection and Diagnostic Overview to cancel the ALL INJECTORS STOP function on the HDS.