Test compression pressure

AR01.00-P-1200AK

Test compression pressure

9.3.07

23.5.05

"Crank engine over ignition switch" is replaced by "Crank engine over contact switch"

23.5.05

Remove throttle valve actuator - no longer required

 

Remove/install

 Danger!

Risk of accident caused by vehicle starting off by itself when engine is running. Risk of injury caused by contusions and burns during starting procedure or when working near the engine as it is running

Secure vehicle to prevent it from moving by itself.
Wear closed and snug-fitting work clothes.
Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

1

Warm up engine to normal operating temperature (approx. 80°C) and switch off engine

 Only test compression pressure when engine is at normal operating temperature.

2

Remove transmitter key from electronic ignition switch control unit

3.1

Remove intake air temperature sensor

with engine 266.920/940/960

AR07.52-P-1465AK

3.2

Remove charge air temperature sensor

Engine 266.980

AR07.52-P-1466BK

4

Remove purge control valve

Engine 266.920/940/960

AR47.30-P-8252AK

Engine 266.980

AR47.30-P-8252BK

5

Remove spark plugs (R4)



Replace spark plugs

AP15.10-P-1580AK

6

Fold up floor covering at the right front

 Do not remove right front seat. Only loosen floor covering until relay and fuse box and battery in the front passenger footwell is accessible.

AR68.20-P-2070AK



Checking

7

Connect compression recorder (1)

AR01.10-P-0010-01AK

 Compression recorder

*001589762100

 Electrical connection set

*220589009900

8

Crank engine over the contact switch for compression recorder (1) for about 5 seconds to remove combustion residues from the cylinders

 Compression recorder

*001589762100

 Electrical connection set

*220589009900

Connection piece

*266589006300

9

Insert compression recorder (1) with connecting piece (2) into spark plug bore

 Compression recorder

*001589762100

 Electrical connection set

*220589009900

Connection piece

*266589006300

10

Crank engine with contact switch for the compression recorder (1) until an increase in pressure is no longer indicated on the compression recorder (1)

 Compression recorder

*001589762100

 Electrical connection set

*220589009900

Connection piece

*266589006300

11

Carry out test procedure at remaining cylinders in the same way

12

Compare measurements obtained with the specified pressures

Compression installation tolerance or new value

*BE01.00-P-1001-01I

Compression pressure wear limit or limit value

*BE01.00-P-1002-01I

Compression pressure permissible difference between individual cylinders

*BE01.00-P-1003-01I

 If the measurement is below the wear limit or if the permissible difference between individual cylinders is exceeded: 

Inspect cylinders for leaks

AR01.00-P-1300AK

13

Install in the reverse order

14

Read out fault memory



Connect STAR DIAGNOSIS and read out fault memory

AD00.00-P-2000-04AK

Number

Designation

Engine
266.920/940/
960
ε=11.0

Engine
266.980
ε=9.2

BE01.00-P-1001-01I

Compression installation tolerance or new value

bar

13.5 to 17.5

13.5 to 17.5

BE01.00-P-1002-01I

Compression pressure wear limit or limit value

bar

12

12

BE01.00-P-1003-01I

Compression pressure permissible difference between individual cylinders

bar

1,5

1,5