Checking holding pressure, engine codes CDLG, CAVB, CAVC, CAVD, CBZA, CBZB, CTHD, CTKA — VW

🧭 Before you start

Fits: VW Golf VI (5K, 2008–2013); platform code 521

• Renewed: fuel filter, fuel delivery unit

Don't miss

• The fuel pump is now actuated to build up fuel pressure.If the final control diagnosis is to be carried out several times in succession, it may be necessary to start the engine briefly before repeating the final control diagnosis.
• Ensure that drain tap (C) on pressure tester(1) is closed.
• Search for leak on engine side. Repeat holding pressure check. This time, close shut-off tap (A) to check whether leak actually is on engine side.
• Ensure plug-in connectors are secured properly by pulling.
• Observe pressure drop on pressure gauge. After 10 minutes, the pressure must not drop by more than 1 bar.

🔧 Engine codes this applies to

📋 Procedure

1. Observe safety precautions .
2. Observe rules for cleanliness .
3. Connect hoseVAS 6550/2 between fuel line from fuel tank to shut-off tap (A) of pressure testerVAS 6550.
4. Connect hoseVAS 6550/1 between fuel line leading to engine and shut-off tap (B) of pressure testerVAS 6550.
5. Actuate fuel pump with final control diagnosis to build up fuel pressure. [Note: The fuel pump is now actuated to build up fuel pressure.If the final control diagnosis is to be carried out several times in succession, it may be necessary to start the engine briefly before repeating the final control diagnosis.]

6. Read fuel pressure on pressure gauge and observe.
7. End self-diagnosis and switch off ignition.
8. Check all fuel lines for leaks and damage.
9. Ensure that drain tap (C) on pressure tester(1) is closed.
10. Shut-off valves (A) and (B) on pressure tester(1) are open.
11. Actuate fuel pump with final control diagnosis to build up fuel pressure.
12. After pressure has built up, close shut-off tap (B) of pressure tester immediately. Lever is then at right angle to direction of flow. [Note: Search for leak on engine side. Repeat holding pressure check. This time, close shut-off tap (A) to check whether leak actually is on engine side.]
13. If there is a leak on engine side, carry out external check of fuel pipes and high-pressure pump for leaks.
14. Remove spark plugs. Open shut-off valves (A) and (B). Actuate fuel pump with final control diagnosis.
15. Check through spark plug holes whether fuel has collected on piston crown due to a leaking injector.
16. Pull fuel supply line (arrow) off fuel filter. Separate plug-in connectors .
17. ⚠ The fuel line is under pressure.Risk of injury to eyes and skin from fuel.Wear eye protection and protective clothing to avoid eye injuries and skin contact. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully opening the connection point. — Connect pressure testerVAS 6550 between fuel filter and fuel supply line using hoseVAS 6550/1 and hoseVAS 6550/2.
18. Connect hoseVAS 6550/2 to connection (A) of pressure testerVAS 6550.
19. Connect hoseVAS 6550/1 to connection (B) of pressure testerVAS 6550.
20. Ensure plug-in connectors are secured properly by pulling.
21. Ensure that drain tap (C) on pressure tester(1) is closed.
22. Shut-off valves (A) and (B) on pressure tester(1) are open.
23. Repeat holding pressure check .
24. After pressure has built up, close shut-off tap (A).
25. Observe pressure drop on pressure gauge. After 10 minutes, the pressure must not drop by more than 1 bar.
26. Check fuel line leading to engine for leaks.
27. Check fuel filter for leaks.
28. Pressure limiting valve in fuel filter is defective. Renew fuel filter .
29. Remove bench seat General body repairs, interior72Rear seat; Removing and installing bench seat / individual seats.
30. Remove fuel pump control unit J538(2) from cover (1).
31. Unclip right cover (1) at retaining tabs (arrows), using removal wedge3409.
32. Pull fuel line (1) off flange. Separate plug-in connectors .
33. ⚠ The fuel line is under pressure.Risk of injury to eyes and skin from fuel.Wear eye protection and protective clothing to avoid eye injuries and skin contact. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully opening the connection point. — Connect pressure testerVAS 6550 between fuel filter and fuel supply line using hoseVAS 6550/1 and hoseVAS 6550/2.
34. Connect hoseVAS 6550/2between connection (A) of pressure testerVAS 6550 and the fuel delivery unit (1).
35. Connect hoseVAS 6550/1 between connection (B) of pressure testerVAS 6550 and the fuel supply line (2).
36. Ensure plug-in connectors are secured properly by pulling.
37. Ensure that drain tap (C) on pressure tester(1) is closed.
38. Shut-off valves (A) and (B) on pressure tester(1) are open.
39. Repeat holding pressure check .
40. After pressure has built up, close cut-off tap (B).
41. Observe pressure drop on pressure gauge. After 10 minutes, the pressure must not drop by more than 1 bar.
42. Check fuel line leading to fuel filter for leaks.
43. Remove fuel delivery unit .
44. Check that all hoses are connected (arrows).
45. Check fuel lines for leaks and damage.
46. If pressure retention valve in fuel pump is defective; renew fuel delivery unit .

Other VW procedures

• Removing engine · 41 torque figures
• Removing and installing camshaft – VW Golf Cabriolet · 47 torque figures
• Adjusting valve timing – VW Passat B5 · 83 torque figures
• Removing and installing camshafts – VW Passat B6 · 39 torque figures
• Removing and installing coolant pump · 53 torque figures
• Removing and installing main fuse carrier (version 2)
• Draining fuel tank in event of faulty fuel pump, engine codes BTK, CCCA
• Removing and installing handbrake cable from model year 2008
• Removing and installing aerial amplifier R24 · 1 torque figures
• Removing and installing front exhaust pipe with diesel particulate filter, engine code BLS