Table 1. Engine Runs Rough or Is Unstable - Continued.
TEST OR INSPECTION
2. Open the low-pressure fuel pump
Engine Runs Rough or Is
purge valve (Figure 3, Item 2) on
Unstable - Continued
the fuel filter housing (Figure 3,
3. Prime the low-pressure fuel pump
No Air in Fuel System - Close purge
(Figure 3, Item 4) by slowly actuat-
valve (Figure 3, Item 2).
ing the prime pump lever (Figure 3,
Proceed to Test Step 3.
Item 3) until all the air is purged
Air Remains in Fuel System - Close
from fuel system.
purge valve (Figure 3, Item 2) and
replace low-pressure fuel pump
Proceed to Test Step 5.
Figure 3. Low-Pressure Fuel Pump and Purge Valve.