Checking delivery pressure of fuel pump — VW

🔧 Engine codes this applies to

📋 Procedure

1. ⚠ Fuel supply line is pressurised. 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 pulling hose off connection. — Remove engine cover panel .
2. Join hose adapterVAS 6551/5-2 and adapterVAS 6551/5-4.
3. Collect escaping fuel with a cleaning cloth.
4. Pull fuel supply line (arrow) off the high-pressure pump.
5. Connect pressure testerVAS 6551 with lines hose adapterVAS 6551/5-2 and hose adapterVAS 6551/5-3 to fuel circuit.

6. Switch on pressure testerVAS 6551 by pressing On/Off pushbutton.
7. Open shut-off taps (A) and (B) of pressure testerVAS 6551 and close shut-off tap (C).
8. Connect vehicle diagnosis tester and carry out guided function "“Checking electric fuel pump”". [Note: The fuel pump is now activated for 30 seconds.]
9. Take pressure reading on pressure testerVAS 6551. Specification: at least 4.5 bar.
10. Start engine and run at idling speed.
11. Take pressure reading on pressure testerVAS 6551. Specification: at least 4.5 bar.
12. Place pressure testerVAS 6551 onto windscreen so that it can be read from inside of vehicle.
13. Increase idling speed to 2500 rpm.
14. Take pressure reading on pressure testerVAS 6551. Specification: at least 4.5 bar.
15. Reconnect fuel supply line to high pressure pump.
16. Pull off fuel supply line (B). To do this, press the quick-release couplings onto the unions, press in the locking elements (keep pressed) and pull the quick-release couplings off.
17. Connect pressure testerVAS 6551 to lines VAS 6551/1 and VAS 6551/2 in fuel circuit.
18. Collect escaping fuel with a cleaning cloth.
19. Perform pressure measurement as in previous check.
20. renew replaceable filter .
21. Reconnect push-fit coupling to fuel filter.
22. Raise cover of fuel delivery unit.
23. First check that connector (arrow) is fitted securely by pulling connector without pressing catch. The connector can cause a fault if it has not been fitted correctly.
24. Pull off fuel supply line (black or black marking) (3) from fuel delivery unit. [Note: Press in securing ring to release fuel lines.]
25. Collect escaping fuel with a cleaning cloth.
26. Connect connection (A) of pressure testerVAS 6551 with line VAS 6551/1 to open end of fuel delivery unit.
27. Close shut-off valves (B) and (C) of pressure testerVAS 6551.
28. Switch on pressure testerVAS 6551 by pressing On/Off pushbutton.
29. Connect vehicle diagnosis tester and carry out guided function "“Checking electric fuel pump”". [Note: The fuel pump is now activated for 30 seconds.]
30. Read pressure on pressure testerVAS 6551. Specification: 7.2 ± 0.5 bar.

Other VW procedures

• Removing and installing pre-wired wiring harness for unit injectors and glow plugs · 1 torque figures
• Checking charge air system for leaks
• Removing and installing engine speed sender G28 · 1 torque figures
• Adjusting non-contact gap of unit injectors · 1 torque figures
• Emptying fuel tank if it is more than 3/4 full
• Removing engine · 41 torque figures
• Removing and installing camshaft · 47 torque figures
• Adjusting valve timing · 83 torque figures
• Removing and installing camshafts · 39 torque figures
• Removing and installing coolant pump · 53 torque figures