FUEL SYSTEM ABNORMAL CONDITIONS
MALFUNCTION 7: (Continued)
Engine fuel supply pump defective.
Fuel Pressure Check
Install pressure test gauges:
100 psi gauge in fuel/water separator filter cover bleeder valve
opening (WP 0084, Fuel/Water Separator Automatic Drain
System and Wiring Harness Replacement).
10 psi gauge in primary filter cover bleeder valve opening
(WP 0086, Primary Fuel Filter Repair and Element
Turn master and in-tank fuel
pump switches "ON".
40 psi at fuel/water separator Primary filter restriction.
Operate engine at high-idle
Element dirty or clogged.
speed (2500-2640 rpm).
filter, and below 1 psi at
primary fuel filter.
a. (Continued) Fuel pump failure (insufficient (2) Repair or replace defective fuel pump
fuel output due to defective regulating
assembly (refer to pertinent fuel pump
valve, internal pump wear or shaft seal leak
causing fuel leakage into engine oil).
(3) Drain oil and replace filters in engine
(WP 0031, Engine Oil Replacement, and
WP 0073, Oil Filters Replacement).
Fuel injector nozzle defective.
a. Abnormal spray pattern (sticky action, stuck (1) Locate faulty cylinder as follows:
partially open, or orifices partially plugged).
Cylinder is not firing due to
Note cylinder on which no
Perform High Pressure Fuel
Check on one cylinder at a time change in engine operation
occurs, or if cylinder misfire
with engine idling (all engine
Note if cylinder temperature is A cold cylinder indicates the
Alternate check with power
cylinder is not firing due to
pack removed. Operate engine cold (by touch) at intake port
area of cylinder head.
at idle speed.
WP 0020 00-9