Volkswagen Workshop Service and Repair Manuals

Fuel Pressure: Specifications

Fig. 1  Thermo time switch triggering time

Control pressure, cold (immediately after starting) ..... see "WARM UP REGULATOR" in DIAGNOSIS AND TESTING.

Control pressure, warm ......................................................................................................................................................... 3.4 - 3.8 bar (49 - 55 psi)

System pressure ..................................................................................................................................................................... 4.7 - 5.4 bar (68 - 78 psi)

Leak test (min. residual pressure) 3.0 bar accumulator:

after 10 min ..................................................................................................................................................................................... 2.6 bar (38 psi)
after 20 min ..................................................................................................................................................................................... 2.4 bar (35 psi)

Thermo-time switch activation period ............................................................................................................................................... See Chart, Fig. 1.

Cold start valve:

min voltage ................................................................................................................................................................................................ 11.5 vdc
injection time ............................................................................................................................................................. see thermo-time switch chart

Auxiliary air reg min voltage ............................................................................................................................................................................ 11.5vdc

Control pressure regulator:

min voltage ................................................................................................................................................................................................ 11.5 vdc
heater resistance ................................................................................................................................................................................. 16 - 22 ohms

Fuel injectors:

opening pressure .............................................................................................................................................................. 3.5 - 4.1 bar (51 - 59 psi)
difference between injectors .......................................................................................................................................................... 0.6 bar (8.5 psi)

Air preheat thermostat

open below .......................................................................................................................................................................................... 20°C (68°F)
closed below ........................................................................................................................................................................................ 34°C (93°F)