Replacing the crankshaft position sensor

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Thanks to Chris Bruno for this :

(By the way, there was NO procedure for doing this in the Helms manual, yet there was a procedure, a shoddy one but one nonetheless, listed in the Chilton's manual. Go figure)

1. (An afterthought) Loosen crankshaft pulley bolt. See step 8-9.

2. Remove battery and battery tray.

3. Remove front engine strut brace and bracket. (These two steps aren't necessary, but they make the job SO much easier. By taking these off you wouldn't believe how much more room it makes in your engine compartment.)

4. Unplug the two connections to the DIS module and then remove the intake manifold resonance chamber connector. Just loosen the 4 screws on the hose clamps and take the two bolts on the top side of the connector out and you should be able to 'wiggle' the connector out of the rubber fittings.

5. Remove the two serpentine belts. To do this you will need to loosen the tension on each belt. To relieve the tension you need to loosen the tensioner pulley bolt (there are two, one for each belt) and then you will need to use the allen head screw that is at the top of each tensioner assembly to loosen the belt. This may sound confusing without looking at the car, but, the belt for the air conditioning and air pump will tighten by the pulley moving down. The belt for the P.S. pump will tighten with the pulley moving up. However, in Ford's wisdom (and I do applaud them for this, once I figured it out) they set up the threads on the allen screws such that your normal loosening of a screw will loosen each belt, and tightening each screw will tighten each belt.

6. You may want to remove the pulley for the P.S. pump belt and the whole tensioner assembly for the A.C. belt just to make more room for yourself to get at the timing cover bolts.

7. Remove the upper timing cover. At this point, you should see a wire (actually 4 wires inside of the black plastic sheath) running down the block behind where the timing cover was. This is the crankshaft position sensor wiring harness. Follow these up and unplug the two connectors at the top of the engine. One is a single wire connector that is a ground for noise insulation and the other is the signal connector. After unplugging these, snake the wire down behind the timing belt.

8. Remove passenger's side front wheel and wheel well cover. The wheel well cover can be a pain but with the proper tugging and bending you should be able to pop it out. This will give all you doorjamb waxers a whole new place to clean, especially considering how much SAND poured onto the ground when I removed mine. Removing these gives you a ton of room to get to the things at the lower part of the engine.

9. Remove crankshaft pulley. This is probably the tougher part of the job. You will need a harmonic balancer puller or steering wheel puller to get this off once you get the crankshaft pulley bolt off. To get the crankshaft pulley bolt off you will more likely than not want to use the starter. I have a 1/2" air impact wrench that couldn't budge the bolt even with my 6 HP compressor (11 CFM at 90 PSI). If you have a big 3/4" impact wrench you might be able to get it off but it is awfully easy to use the starter. Just place the socket wrench (I used a 1/2" 19 mm deep socket) and rest the handle of the wrench on the frame rail to the front of the car (in front of the pulley, that is). Then just bump the starter and I mean just BUMP. It really takes no more than a tap... you will hear a loud clunk as the slack in the wrench is taken up by the slamming of the wrench into the frame rail and then Viola! the nut will be nice and loose. NOTE: You may want to do this first, before removing the battery. After this bolt is off, just use the puller with 2.5" long M8 hex head screws and take the pulley off.

10. Remove the lower timing cover off. When doing this, note the location of the different length screws.

11. Now you should clearly see the sensor. You can remove these two screws (They seemed pretty tight to me) and then remove the sensor and wiring. One of the most difficult parts was removing the wire from the 'snap fit' in the middle timing cover assembly. The Chilton's manual suggested to remove the middle cover, but you can't do this without remove one bolt on the P.S. belt tensioner assembly that was a real PITA to get to so I just dealt with it in place. To get the wire out just pull at it and wiggle it until it pops out. IT is tough, though.

12. If you can't remove the sensor (the screws are out but the sensor won't come out) then the sensor is 'stuck' in one of the vanes on the vane 'ring' that is on the crankshaft. The Chiltons manual says to turn the crank by hand - HA! Yeah, right, and I can bench press 800 pounds too. What I found was real easy for turning the motor was to place the lug wrench in between two lugs on the passenger's side hub and then put the car in fifth gear and turn the driver's side wheel (assuming the whole front end is off the ground). Of course this won't work if you have an automatic so you may have to put the crank pulley back on and use leverage in between the two removal bolts to turn the crank. Just make sure you turn it the right direction and have extra removal bolts as spares since you will probably bend them.

Now, the sensor is out. Here are some installation tips:

1. After installing the new sensor, you need to adjust the gap between one vane and the sensor. To do this, you will have to rotate the crank after the new sensor is in so that there is a vane in place, so to speak and then measure this gap. The gap should be 0.8mm / 0.03 inch.

2. To install the crank pulley, I used a small piece of a 2"x4" and a hammer to tap the pulley in far enough that I could just use the crank pulley bolt to pull it in the rest of the way. I had bought an M14 bolt to use for this task but the threads are NOT M14. I'm not quite sure why they use a standard thread or worse, a rare M13 bolt, but I didn't bother to measure it. It is not preferred to tap the pulley on due to the thrust loads on the crank bearings, but people have been doing it for decades with seemingly no ill effects.

3. Installing the wire of the sensor back into the 'snap fit' that I referred to earlier was a BIG PITA. What I found worked the best is to apply a little grease to the rubber housing (you'll see what I mean if you ever take one out) and then snap it in with the male end of a 1/4" socket extension.

4. Other than this everything is the reverse of the removal steps. Make sure you tighten the serpentine belts properly upon reinstallation. Now would also be a good time to change them if they look old or worn.

5. The above steps are identical to what you need if you are changing the timing belts or the water pump (except for a few extra steps at the end). After doing this once, I suspect I could probably do the whole job in less than 3 hours if I had everything in front of me and didn't dilly-dally (as I normally do when I'm not rushing to finish). Also, I think I only cursed once - that must be a new record for me when working on my car!