So you may own a 2009-2011 Ford Fusion/Mercury Milan, and you may have a MIL (Malfunction Indicator Lamp) lit up (may look like a wrench), and randomly you may experience a stalling issue or loss of power, leaving you stranded on the side of the road.

Owners are reporting that the vehicle will idle fine, but the throttle is unresponsive or that when trying to accelerate the engine sputters badly and the car barely moves. Some owners state that if they shut the ignition off and restart the vehicle, everything is fine for a while before it happens again.

Whether you own the 2.5L 4-cylinder or the 3.0L V6, you are not alone. This is a common, and known problem with these vehicles. Ford hasn’t done anything about it regarding recalls, but they are aware of the issue and have issued a TSB (Technical Service Bulletin) on it. In fact, it covers a lot of vehicles and engines (see TSB 10-21-6). They’ve also updated the replacement part so that this should not happen again with the new part.

The trouble codes that set are a P2112 TAC System Stuck Closed, and a P2111 TAC System Stuck Open. The throttles on these cars are a drive-by-wire system, meaning it’s an electronic system that drives a small electric motor on the throttle body that opens and closes the throttle body. When these codes are set, the throttle body isn’t opening, hence the lack of throttle response.

I’ve taken a post from a Ford FE engine forum which describes the diagnostic procedures to test whether or not the throttle body is defective:

You will need a scan tool that can access the data for the throttle position sensors. First check is does the plate open fully with KOEO and pedal on floor. If it does, look at the data for TP1 and TP2. TP1 should be 3.7v to 4.7v and TP2 should be .3v to 1.9v pedal released. Pedal floored TP1 should be .7v to 2.9v TP2 should be 4.1v to 4.7v. If that’s what you see, wiggle the harness from the PCM to the TB. If the voltages stay between .49v and 4.65v and don’t jump around, replace the TB.
If you have warranty, I’d let the dealer do it. You won’t like the price of that TB…

If you end up having to replace your throttle body, it’s best to have a shop do this, but if you decide to replace it yourself, I found a helpful video on youtube which shows the procedure with a 2011 Fusion 3.0L V6:

As stated in the previously linked video, replacing it yourself could save you a bundle in labor costs, but if not done properly could lead to other problems. Having an auto mechanic you can trust repair the vehicle for you will save you time and headaches, and a possible tow bill to a shop after you get it halfway torn apart and decide that you can’t do it.