WarningObserve the safety and cleanliness recommendations
Recommended tools
[1] compression tester MULLER 203 102-100
[2] dummy spark plug (-).0194-G
[3] leakage tester FACOM 910.A
[4] diesel engine adaptor FACOM 910.A6
[5] flywheel stop (-).0194-W
Removing
WarningRespect the safety and cleanliness recommendations that are specific to high pressure diesel injection (HDi) engines
Ensure that the speed of engine rotation, driven by the starter, is correct (minimal value: 250 rpm)
NoteChecking is carried out with the engine cold
Remove
- The battery style cover
- The pre-heater plugs
Disconnect
- The battery
- The engine management ECU
Isolate the pre-heat plugs supply wire
Measuring the pressures at the end of compression
Fit the tool [2]to cylinder N° 1; tighten to 1 ± 0,1 daN.m
Connect the tool [1]to the tool [2]
Reconnect the battery
Operate the starter for 10 seconds (engine management ECU disconnected)
Measure the pressure at the end of compression, in order, on cylinders 1, 2, 3 and 4: the maximum difference between any 2 cylinders should be 5 bars
WarningIf the pressure values are low, check the condition of the air filter and the head gasket before planning an engine overhaul
Compression loss measurement
WarningChecking is carried out with the engine cold
Place the vehicle on a lift
Disconnect the battery
Remove the under engine protection
Set the timing belt
Determine which cylinder is at end-of-compression phase; using the tools [2], [3], [4]
Insert the flywheel stop [5] (at "a" and "b")
Tighten the bolt (1)
Read the loss of compression; using the tools [2], [3], [4] (average value = 20%)
NoteA considerable compression leak results in noise, or causes air bubbles to rise in the cooling system
If the value is incorrect, faulty parts can be located by locating the noise made by the passage of air
| diagnosis | check the condition of the following components |
|---|---|
| air leak: air inlet manifold | inlet valves |
| air leak: exhaust manifold / exhaust system | exhaust valves |
| air leak: Oil filler cap / oil gauge well | pistons / piston rings |
| air bubbles: cooling system | cylinder head gasket / cylinder head |
Carry out the same operation for the 3 other cylinders, each time rotating the crankshaft halfway by using the pulley/casing identification marks
Refitting
Remove the tools [1], [2], [3], [4], [5]
Reconnect
- The engine management ECU
- The battery
Refit
- The protective panel under the engine
- The pre-heater plugs
- The battery style cover
WarningPerform the operations to be carried out following reconnection of the battery