900 L4-1985cc 2.0L SOHC (1988)
Fig. 4 Control pressure specifications
Carry out this test if poor engine performance has been experienced during cold starting and warming up period. Engine must be cold. Do not run
before test.
1.
Open valve and disconnect plug at warm-up regulator.
2.
Turn on ignition and compare pressure gauge reading with recommended pressure given in Fig. 4.
3.
If values differ, replace warm-up regulator.
Warm Engine Control Pressure
Carry out this test when poor performance has been experienced when the engine is warm.
1.
Open valve and connect warm-up regulator plug.
2.
Leave ignition on until rest pressure is 48.5-54.0 psi (3.4-3.8 bar).
3.
If value differs, replace warm-up regulator.
Line Pressure
1.
Close pressure gauge valve.
2.
Operate the fuel pump.
3.
Line pressure should not vary from a test value of 64.0-72.5 psi (4.5-5.1 bar) or a setting value of 66.9-69.7 psi (4.7-4.9 bar). Excessive line
pressure may be caused by a blocked return pipe or faulty line pressure regulator. Insufficient pressure may be caused by insufficient fuel
pump pressure, blocked fuel filter, leak in fuel pipe, or a faulty line pressure regulator.
Leakage Test
This test should be performed if warm starting performance is unsatisfactory.
1.
If engine is cold, bi-metal strip in warm-up regulator must be heated and kept warm during the test.
2.
Remove connector on warm-up regulator, and replace it with one connected directly to battery.
3.
Open pressure gauge valve.
4.
Activate fuel pump until reading is 48.5-54.0 psi (3.4-3.8 bar). Disconnect pump. Generally a leak becomes evident within 3-4 minutes.
5.
Maintain system pressure for 20 minutes. The minimum system retained pressure should be 22 psi (1.5 bar). If the pressure falls too rapidly, the
fault can be localized by performing the test with the valve shut. If figures obtained from this test are correct, then the warm-up
regulators' stop valve is faulty. If the pressure drop is still excessive, the following components could be faulty, fuel pump check valve,
fuel distributor, or cold start valve.
NOTE: Leaks can occur if the "O"-ring in the line pressure regulator is damaged.
