Replace a Camshaft Position Sensor 1997 Ford Taurus

*-* Click images for Huge Pictures

Foreword

The Ford Taurus is starting to get old but it's had very few problems in its 130k+ life, I had the check engine light flash at me today to find out the camshaft position sensor is throwing a fault and causing a misfire (thanks to Autozone for the free check engine light scan). It turns out that the camshaft position sensors are built with a small strong magnet in the sensor and a pickup at the perimeter, eventually the magnet falls out of the sensor and rips things up pretty well, requiring a full replacement of the distributor drive train and encoder pickup sensor.

Step One: Make Sure Your Sensor is Bad

In my case the check engine light started flashing, the engine started misfiring (audibly putting), codes were thrown for random misfire and camshaft position sensor. Further corroborating evidence was when I peered below the throttle body to find pieces of the sensor laying about on the top of the engine block and the wires leading to a quarter of the sensor.

Step Two: Clear the Path

The only difficult part about this repair is clearing the path to the distributor, after you get there it's not difficult to roughly index the distributor and pull it out/swap in a new one. The distributor is located directly below the throttle body, so you'll want to remove:
  • Positive battery terminal
  • Plug wires for cylinders 1,2,3 (just disconnect from the coil)
  • Oil blowby tube (oil fill cap to just upstream of the throttle body)
  • Cover over the throttle body cables - 8mm, 2 screws
  • 4 bolts that hold the throttle body on (bottom two have nuts holding those plug wires in place, they were really tight on mine, I had to take the hole bolt off and remove the nuts after getting the throttle body out of the way) - 8mm socket, 2 nuts, 4 machine screws
  • Hose clamp holding the Mass AirFlow (MAF) sensor to throttle body tube in place
  • Pull the 3 plug wires and the throttle body assembly aside now
  • Take the cover off or just pull aside the wiring tray directly above the distributor
Image Notes
1. Remove the throttle body bolts, tap it with a dead blow (rubber) hammer until the gasket breaks loose.
2. Loosen the hose clamp holding the intake air tube to the MAF Sensor.
3. Should look like this when everything is loosened up.

Step Three: Pull Distributor and Replace

FIRSTLY, YOU MUST INDEX/NOTE THE POSITIONS OF THE BODY AND ENCODER!

You don't have to place the engine in any particular position (Top Dead Center [TDC], etc) as long as you index/mark/note the position of the distributor housing and the encoder (inside under the sensor cover). You must, absolutely must, replace the distributor in the same orientation as you removed it. You can also find/purchase the Ford tool that can be used to align the distributor to the engine for optimal performance (timing), engine ran fine after I replaced mine and eyeballed it but YMMV.

You should have everything out of the way and be able to see the top of the distributor. I used a prybar but you may want to use a slide hammer on the 2 small screws (5.5mm, yeah, that's right, 5.5mm) holding the sensor in place. Hopefully you get the distributor moving out of the block.

Installing the new distributor may be interesting, the distributor I picked up from Autozone was rough cast and not finish machined anywhere, this led to interference between the block and the distributor that had to be filed off (picture 4 below). After filing the distributor slide in with a little assistance from a rubber mallet.

After you get everything buttoned up plug the battery back in a fire up the engine, hopefully you won't have a check engine light and everything should be running well. Good Luck!
Image Notes
1. Wrecked camshaft position sensor.
2. Clearly destroyed.
3. Replacement looks nice, have to eyeball alignment with the old one due to the damage.
4. Had to file down the edge of the new distributor to fit into the block.
5. Looking happy in its new home!