Camshaft, Lifters and Push Rods: Testing and Inspection

Camshaft adjustment, checking
The camshaft adjustment is load- and RPM dependent. The electrical valve for camshaft adjustment switches oil pressure onto camshaft adjuster (mechanical adjustment mechanism), which adjusts the camshaft.

Special tools and equipment
^ VAG1551 scan tool (or VAG1552 mobile scan tool) with VAG1551/3 cable
^ VAG1526 multimeter or VAG1715 multimeter

Checking activation
- First check activation of the solenoid valve for camshaft adjustment via the Output Diagnostic Test Mode (DTM):
Refer to Powertrain Management.
If activation is OK:
Check solenoid valve





- Measure resistance between terminals of solenoid valves.
Specification: 10 to 18 ohms
If no malfunction can be detected at valve:
- Check function of camshaft adjustment.

Function of camshaft adjustment, checking
If special testing equipment is required during road test, note the following:
^ Test equipment must always be secured to the rear seat and operated from there by a second person.
If test and measuring equipment is operated from the passenger seat, the person seated there could be injured in the event of an accident involving deployment of the passenger-side airbag.

Test requirement
^ Coolant Temperature at least 80°C

Note: To test camshaft adjustment, vehicle must be driven. Doing this requires a second person.

WARNING! Secure Scan Tool (ST) on the rear seat and have operated from there by second technician.

Test sequence
- Connect VAG 1551 scan tool (VAG1552). Start engine and select the Engine Control Module (ECM) using address word 01.
Refer to Powertrain Management.





Indicated on display:
- Press buttons -0- and -8- to select "Read measuring value block" function 08. Press -Q button to confirm input.





Indicated on display:
- Press -0-, -9-, and -4- for "Display group number 94". Press -Q- button to confirm input.





Indicated on display: (1 to 4 display fields)
- Observe indication in display field 2.
Specified value (engine at idle):
AUG Engine: Cam. pos. OFF
AWM engine: CAM-ADJ. ON
- Accelerate vehicle from stand-still in 1. gear or driving mode 2. Camshaft adjuster must be active between 1800 to 3200 RPM.
Specified value (display field 2): Cam. pos. ON
Specification (display field 4): Sys. OK
- Press (arrow) button.
- Press 0 and 6 for the function "End Output", and then press Q to exit from input mode.
- Switch ignition off.
Check DTC memory if display field 4 indicates "System. not OK".
Refer to Powertrain Management.
If a malfunction is indicated, the following malfunction can occur:
The solenoid valve for camshaft adjuster properly switches the oil pressure to the mechanical camshaft adjuster, however the adjuster cannot reach its end position (e.g. due to difficulty of movement).
- Replace camshaft adjuster.