Injector Leak Down Test

Note:
The best way to resolve a Code 45 or driveability incident is to carefully go through ALL the steps contained within this bulletin.

Performed with the fuel pressure gauge still connected

A. Turn the ignition switch "ON" to cycle the fuel pump on for 5 SECONDS.

B. Turn the ignition switch "OFF" after 5 SECONDS.

C. Use fuel hose pinching pliers and pinch off the inlet hose between the fuel filter and the gauge, also pinch the outlet hose between the fuel pressure regulator and the hard line returning to the fuel tank.

D. Monitor the fuel pressure gauge every 5 minutes.





E. Compare the time and amount of fuel pressure drop to chart 1.

Note:
An initial rise in pressure of 2-5 PSI is normal.


Note:
If there is an actual leaking injector(s), the fuel pressure will fall to 0 PSI within about 10 minutes. The time will depend on the severity of the leak or the number of injectors leaking.

INJECTOR FOUND: CONTINUE TO STEP 5

INJECTOR DETERMINE TO BE LEAKING:
AFTER REPLACING THE LEAKING INJECTOR(S) CONTINUE TO CHECK FOR SENSORS THAT CAN CAUSE A RICH CONDITION. REPLACE THE ENGINE OIL AND ENGINE OIL FILTER BECAUSE OF FUEL IN OIL.