7.3L Power Stroke Cam Position Sensor (CPS)

How to Change the CPS on a 7.3L Power Stroke

A bad camshaft position sensor (CPS) may cause a choppy/rough idle, stalling, hard starting, or no start condition on the 7.3L Power Stroke. This may or may not be accompanied by a check engine light (and corresponding diagnostic trouble code). The sensor is difficult to access, but with the right tools and procedures it can be replaced in mere minutes. It is recommended that you only use cam position sensors directly from Ford or International, as aftermarket or generic brand sensors tend to be less reliable. Motorcraft DU-87 cam sensor (Ford F4TZ-12K073-C) is relatively inexpensive in the grand scheme of things, and it's not a bad idea to keep a spare in the glove box so you don't find yourself stranded.

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7.3 Powerstroke CPS location

• Disconnect both negative battery cables.

• The cam position sensor on the 7.3 Power Stroke is located just above the crankshaft damper at approximately the 11 'o clock position. It is difficult to access and view from the top of the engine bay.

• Removing the serpentine belt will make the cam sensor easier to access, though this step is not required.

CPS electrical connector removed

• We've found the easiest way to access the sensor is from below; the damper is well within reach, even if you choose to leave the belt on.

• Disconnect the cam sensor connector by slightly prying upwards on the locking tab and pulling downwards at a slight angle towards the passenger side.

Tools to remove 7.3 Powerstroke cam sensor

• A single 10 mm bolt holds the CPS in place. A 10 mm deep socket and 3/8" drive socket wrench fit well in the tight space.

• Remove the CPS retaining bolt and then the sensor itself. Rotate the sensor side-to-side slightly while pulling outwards from the engine block and it should slide right out.

Lubricating the cps o-ring

• To ensure a positive seal of the new sensor, lubricate the o-ring of the new sensor with a liberal amount of fresh engine oil.

• Install the new CPS in reverse order, twisting it side-to-side while pushing it into the engine block, then reinstall the retaining bolt.

CPS location with sensor removed

• Reinstall the sensor's electrical connection, reconnect the negative battery cables, and start the truck to ensure that the new sensor was installed correctly and is functioning properly.

• The image at left shows the cam position sensor location with the sensor removed.