Cylinder Combustion Pressure Leakage
WARNING: This page is about a different car, the 2003 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
The combustion pressure leakage test provides an accurate means for determining engine condition. Combustion pressure leakage testing will detect exhaust and intake valve leaks, improper seating, leaks between adjacent cylinders or into water jacket, or any causes for combustion/compression pressure loss.
- Check the coolant level and fill as required. Do not install the pressure cap. Start and operate the engine until it attains normal operating temperature, then turn the engine off. Clean spark plug recesses with compressed air. Remove the spark plugs. Remove the oil filler cap. Remove the air cleaner.
- Calibrate the tester according to the manufacturers instructions. The shop air source for testing should maintain 70 psi (483 kPa) minimum and 200 psi (1379 kPa) maximum. The recommended air pressure is 80 psi (552 kPa).
- Perform the test procedures on each cylinder according to the tester manufacturer's instructions. Set piston of cylinder to be tested at TDC of compression stroke. While testing, listen for pressurized air escaping through the throttle body, tailpipe and oil filler cap opening. Check for bubbles in the radiator coolant. All gauge pressure indications should be equal, with no more than 25 percent leakage. For example: at 80 psi (552 kPa) input pressure minimum of 60 psi (414 kPa) should be maintained in the cylinder. If pressure is not as specified, diagnose pressure loss.