Any new car release is going to have growing pains as it settles into customer hands. All the testing in the world just can’t find or fix some problems. It is all about how the brand responds to these problems that really matters. In Ford’s case, they have been on top of any potential problems for the 2011 Mustang, already issuing one Technical Service Bulletin for problems with the Mustang’s clutch pedal.

Mustangs Daily reports that Ford has issued a second TSB for both V6 and V8 Mustangs regarding the Fuel Pump Module (or FPM).

The symptoms of this problem are more of an annoyance than a serious issue. Some Mustang owners might notice the fuel gauge plummeting from ½ a tank to a ¼ tank to E very quickly. This has to do with the FPM, which may not be reading the right amount of fuel left in the right hand side of the tank. The Mustang utilizes a saddlebag-style fuel tank that straddles the driveshaft tunnel. The FPM is an electric fuel pump and fluid sensor level, located on the left side of the tank. Another fluid sensor and a fuel pump pickup are located on the right hand side.

The FPM draws fuel from the right hand side first, and then the left. The problem is that the FPM may be reading the levels of fuel wrong, assuming that since the right hand side is empty, or the whole tank might be empty. This sends the fuel gauge plummeting, even though the Mustang still has anywhere from 5-8 gallons of fuel left. The repair replaces the fuel pump, and the service is covered under warranty and should take a professional just an hour to do.

Ford is doing right by its customers by staying ahead of these problems before many of us even here about them. Kudos Ford, kudos.

Official TSB

Service Procedure:

Mustang has a saddle type fuel tank in that there is a hump in the middle of the fuel tank for the driveshaft.

There is one electric pump and fuel level sensor (FL-1) on the LH (driver side) of the fuel tank, this is the FPM.

There is a fuel pick up and fuel level sensor (FL-2) on the RH (passenger side) of the fuel tank.

The system draws fuel first from the RH side of the tank. The FPM siphons fuel from the RH side of the tank via the fuel pick up. Once the fuel level on the RH is too low to siphon fuel, there are check valves that close and the fuel will now be drawn from the LH side of the tank via the FPM.

The fuel level senders read the fuel levels on both sides of the tank. The two values are averaged for display on the fuel gauge. The fuel gauge system will drop the fuel gauge indicator to E if it sees a large difference in the fuel levels from RH (FL-2) to LH (FL-1) fuel level sensor. The system is expecting the RH (FL-2) side of the tank to go down before the LH (FL-1). Sending the fuel gauge indicator to E and having the message center low fuel warning turn on warns the customer that he may run out of fuel. Replace the FPM. Refer to Workshop Manual (WSM), Section 310-01.