Residual Pressure Test

Fig. 20 Removing fuel pump non-return valve:

1. When warm engine control pressure is reached, shut off fuel pump and note pressure drop. After 10 minutes, pressure should be at least 39.2 psi. After 20 minutes, pressure should be at least 37.7 psi.
2. If residual pressure drops too quickly, proceed as follows:
a. Retighten all fittings and connections in fuel circuit.
b. Check cold-start injector for leaks.
c. Check injectors for leaks.
d. Remove and clean fuel pump non-return valve (1) Fig. 20, using tool 8.0141 BA.
e. Remove and clean supply pressure regulator and replace if necessary.
f. Replace fuel accumulator.