Diagnosis Of "Water In Fuel" Light - GMC G Service Manual

DIAGNOSIS OF "WATER IN FU EL" LIGHT
PROBLEM
Intermittent Light
Light Stays On With
Engine Running
(Temperature Above
Freezing)
Light Stays On With
Engine Running
(Temperature Below
Freezing)
Light Comes On At
High Speed Or During
Heavy Acceleration
Light Stays On
Continuously And
Engine Stalls And
Will Not Restart (After
Initial Start>Up)
Light Stays On
Continuously And
Engine Stalls And
Will Not Restart (After
Refueling)
ENGINE. DRIVEABILITY AND DIAGNOSIS 6A-7
POSSIBLE CAUSE
Water in fuel filter.
Fuel filter is clogged or contains water.
Fuel filter is clogged with ice.
Plugged fuel filter.
Fuel filter or lines plugged.
Large amounts of water pumped into the
tank.
Figure 4 — Diesel Engine "Water In Fuel" Light Diagnosis
CORRECTION
Drain water from the fuel filter.
Drain the fuel filter. If no water is drained and
the light stays on, replace the filter element.
Drain the fuel filter. If no water is drained,
open the air bleed and check for fuel pres­
sure. Replace the filter element if there is no
pressure.
Replace the filter element.
Replace the filter element or check the lines.
Purge the fuel tank.
GMTB-0922-2L