The Ford Fusion uses the same Duractec 3.0L and 3.5L engine versions used in practically every other V6-equipped Ford car or truck, including the Mustang. These engines have been designed to be both versatile and easy to work on for those who specialize in Ford vehicles. If your upper intake manifold is cracked or broken, or you simply want to replace it with a higher flowing unit, be glad to know that installing a new one can be done in as little as a half an hour.
To prevent short circuiting, you'll need to disconnect all of the ancillaries connected to the manifold, starting with the battery. The plastic vanity cover (if so equipped) comes off simply by turning the retainers counter-clockwise and pulling the cover free. The throttle body (the main air intake valve) comes off with the manifold, so remove the engine air intake tube that links the throttle body to the air filter box. To remove it, detach the hose clamps that secure it on either side, then pull it free. Next, disconnect the throttle position sensor attached to the throttle body, as well as the rubber evaporative emissions tube.
If you haven't already noticed, the upper intake is connected to several systems, all of which will need to be removed in order to proceed. To free up the throttle body, remove the accelerator and cruise control cables by pulling them forward until the retainer clears the throttle linkage. Slide the cable retainer out of the throttle cable bracket, then set the cable aside. Disconnect the alternator cable and bracket from the throttle body.
While this step isn't strictly necessary, you may also want to remove the PCV (Positive Crankcase Valve) system from the manifold in order to transfer it to the new manifold. Remove the four bolts that hold the PVC solenoid to the manifold, and remove the PCV tube itself. The PCV tube is the rubber line that connects the throttle body to the back of the engine via a galvanized pipe.
Disconnect all of the vacuum tubes to which you have access, then disconnect the rest of them as you lift the manifold clear of the vehicle. Consider marking the vacuum tubes and their locations with masking tape and a permanent marker. Remove the four bolts that secure the ignition coil, which is located on the back of the upper intake manifold. You do not need to disconnect the coil itself; you only need to unbolt it and set it aside.
The easy part of this removal is unbolting the upper intake's twelve bolts, and pulling it free from the lower intake. For ease of re-installation, you should consider marking the long and short bolts and their locations with a paint pen or dry erase marker. The Fusion's intake uses three different sizes of bolts, so marking them can save a lot of aggravation later.
