Chrysler 1991 Service Manual Supplement page 117

DIESEL FUEL INJECTION SYSTEM DIAGNOSIS
SYMPTOM
CAUSE ACTION
Engine does not rev up Control lever not going to full throttle
position
Adjust throttle linkage
Air in fuel system Bleed fuel system
Intercooler internally blocked or leaking Check pressure drop across intercooler.
If pressure drop is more than 4 in. Hg,
clean or replace as necessary
Clogged fuel filter Replace fuel filter
Restricted or blocked fuel supply lines
Remove restrictions or replace lines
Wax buildup in fuel filter (cold weather
only)
Inspect fuel heater electrical connector
for damage. Replace fuel filter, use
recommended diesel fuel.
Incorrect injection pump timing Adjust injection pump timing
Injection pump overflow fitting switched
with inlet fitting
Install fittings in proper sequence
Low or uneven engine compression Repair as necessary
Fuel injection pump malfunction or
not adjustable
Replace injection pump
injection pump runs hot Overflow blocked Clean overflow orifice or replace fitting
J9114-254