Fuel Pump - Hissing Noise

Article No. 85-4-23

NOISE - HISSING - 5.0L & 3.8L - NORMAL FUEL PUMP

FORD 1985 THUNDERBIRD

LINCOLN-MERCURY 1985 CONTINENTAL/MARK VII

The in-tank high pressure fuel pump on the subject vehicles generates a hissing noise which can be heard outside the rear of the vehicle. The noise sounds like an exhaust or tire leak. This noise is NORMAL. The fuel pump should not be replaced.

This hissing noise can be identified for the customer by employing the following procedure.

1. Place the vehicle in a quiet area.

2. Position customer near fuel filler door.

3. Turn ignition switch from OFF to RUN position. Do not crank the engine. (Fuel pump will run for approximately one second).

4. Cycle ignition switch to OFF position and repeat Step 3 if extra cycles are required to identify the noise. (Some vehicles may require extra time in OFF position to reset the timer).

5. If hissing noise is verified with the customer using the above procedure, explain to the customer that this is normal operating noise for the fuel pump.

OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: "INFORMATION ONLY"