Cylinder Leakage Test
Cylinder Leakage Test
Removal Procedure
Note:
A leakage test may be performed in order to measure cylinder/combustion chamber leakage. High leakage may indicate one or more of the following:
* Worn or burnt valves
* Broken valve springs
* Stuck valve lash adjusters
* Damaged piston
* Worn piston rings
* Worn or scored cylinder bore
* Damaged cylinder head gasket
* Cracked or damaged cylinder head
* Cracked or damaged engine block
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle Service and Repair.
2. Remove the front wheelhouse liner Inner front extension. Refer to Front Wheelhouse Liner Inner Front Extension Replacement .
3. Set up the crankshaft.
4. Move the crankshaft in the direction of the engine rotation to the first cylinder TDC position (mark 1).
5. Lower the vehicle.
6. Remove the timing belt upper front cover. Refer to Timing Belt Upper Front Cover Replacement Timing Belt Upper Front Cover Replacement.
7. Remove the spark plugs. Refer to Spark Plug Replacement Service and Repair.
8. Detach the engine wiring harness from intake manifold, cylinder head cover and engine wiring harness bracket.
9. Remove the coolant expansion tank closure cap.
10. Remove the oil dipstick.
11. Apply guidance marks.
12. Attach 3 markings (2) as an aid to one of the camshaft adjusters, each one offset by 90° to the marking applied (1).
Test Procedure
Note:
Follow manufacturer instructions.
1. Calibrate the pressure loss tester and connect to the compressed air system.
2. Install the pressure loss tester.
Note:
Wheels must be in contact with the ground.
* Engage first gear and apply the parking brake.
* Install the connecting piece into the spark plug thread of cylinder number 1.
* Apply compressed air to cylinder number 1.
3. Inspect for Pressure Loss
* Take pressure loss reading.
* The maximum permissible pressure differential between cylinders is approximately 10 percent.
* Maximum pressure loss of a cylinder is 25 percent.
4. Take note of any visible escape of compressed air. In excessive leakage situations, inspect for the following conditions:
* Air leakage sounds at the throttle body, intake manifold or air inlet hose that may indicate a worn or burnt intake valve or a broken valve spring.
* Air leakage sounds at the exhaust system tailpipe that may indicate a worn or burnt exhaust valve or a broken valve spring.
* Air leakage sounds from the crankcase, oil level indicator tube, or oil fill tube that may indicate worn piston rings, a damaged piston, a worn or scored cylinder bore, a damaged engine block or a damaged cylinder head.
* Air bubbles in the cooling system may indicate a damaged cylinder head or a damaged cylinder head gasket.
5. Perform pressure loss test by analogy on cylinders 3, 4 and 2.
Installation Procedure
1. Remove the pressure loss tester.
2. Remove the connection piece from the spark plug thread.
3. Put the vehicle in neutral.
4. Insert the oil dipstick.
5. Install the coolant expansion tank closure cap.
6. Install the spark plugs. Refer to Spark Plug Replacement Service and Repair.
7. Install the engine management wiring harness to the intake manifold, cylinder head cover and engine wiring harness bracket.
8. Install the timing belt upper front cover. Refer to Timing Belt Upper Front Cover Replacement Timing Belt Upper Front Cover Replacement.
9. Raise the vehicle.
10. Install the front wheelhouse liner Inner front extension. Refer to Front Wheelhouse Liner Inner Front Extension Replacement .
11. Lower the vehicle.