How do you change the Camshaft Position Sensor CMP on a Gen3 Ford Taurus Mercury Sable?

Answer 1

Warning! This part drives your oil pump!DO NOT USE THE DORMAN PART!The Dorman part is poorly manufactured and WILL fail . Use a Genuine Motorcraft or A1Cardone Syncronizer (or sensor). Depending on which you are replacing.

4 of 4 Sensors tested suffered severe damage due to poor quality workmanship and Metallurgy.

DO NOT USE THE DORMAN PART.

The cam synchronizer is a common failure item in Vulcans, with a working life typically between 80-100k miles. It usually doesn't seem to do any damage if caught in time, but as the gear at the bottom of the synchronizer drives the oil pump it could (worst case scenario) theoretically destroy an engine.

There are two causes for the failure. The first seems to be exclusive to the hall effect version of the sensor, (up to 1997), where a piece of the magnetic tab that sits on the underside of the top of the sensor breaks off and damages the vane (metal tab that sticks up out of the rotating assembly that the sensor reads) that is used to time the engine; this will throw a CEL as the sensor is no longer functioning. The second applies to all vulcans and is what actually causes the chirping, it seems that the rotating assembly in the synchro does not receive proper lubrication and the bearings start to fail. In either case the synchro itself will have to be replaced, and it's usually a good idea to replace the (cheap) sensor while you're at it.

The problem manifests itself a chirping coming from the transmission (driver) side of the engine. It can be very hard to pinpoint, when mine started to fail the sound appeared to come from different places as I moved around the engine bay. When my mechanic took a stethoscopey thingy to my engine bay, he concluded that it was ghosts and I should "come back if it gets worse". From reading posts on here, and my own experience, the chirping responds to RPMs, most pronounced at idle and eventually drone out to a whine at driving speed. It also seems to be affected by heat and humidity. Mine stopped making noise (when it got cooler outside) the better part of a year before I replaced it, but I suspect that if I hadn't it would have started again when it got hot.

There's a cheap way to replace the assembly, and an expensive way. From what I've read on here, dealers/mechanics will charge $150-$170 for the assembly, as well as 3-4 hours of labor for the replacement. The actual replacement of the part is as simple as undoing 1 clamping bolt, removing the old assembly and installing the new one. The most time consuming part for me was cutting the plastic tray that guided the wire bundle that ran directly overtop of the assembly so that I could even get to the synchro. Whether you are comfortable with doing this yourself will depend on how stubborn you are, and whether you think you're up to digging your way to the sensor/synchro. That's the hard part.

There is some risk to doing it yourself, but only if you do it incorrectly. The cam synchronizer is integral to engine timing, and if the new assembly is not installed with the exact same orientation as the original some serious damage could occur. Luckily, it's not that easy to mess up if you pay attention. The teeth on the bottom of the synchronizer are big enough that the vane rotates approx 10 degrees for each tooth. After removing the sensor from the top of the assembly and before touching the clamping nut that secures the synchro; if you mark the relative position of the synchronizer body on the block, and mark the position of the vane on the synchro body you can install the new synchro in the exact same position. If you make accurate marks and pay attention, it will be obvious if you are off. I replaced mine with this method and have driven approx 150 miles since without a CEL to be seen, nor a squeak to be heard.

Good luck, I saved myself several hundred dollars doing this myself with information gleaned from the TCCA. Even if you choose to have a mechanic or dealer do the replacement, diagnosis and correction of this issue could save you some money and trouble in the long run.

--Earthsick from TCCA

To replace the Syncronizer:(Do this if you have inexplicable, "impossible to find", chirping or squeaking that may or may not increase pitch or frequency with engine RPM's. Your Syncronizer is failing.)

Locate the cam synchronizer there should be a small coolant hose above the harness disconnect the hose pull the spark plug wires from the coil move them out of your way lift up on the wiring harness shroud there are two 5.5 mm bolts holding the sensor to the synchronizer remove the bolts remove the sensor mark the location of the synchronizer on the block and there is a tit inside the synchronizer mark its location to the synchronizer body now remove the 10mm bolt holding the synchronizer to the engine pullup twist counter clockwise it should come right out then get your new synchronizer make the same alignment marks on the new one as you marked on the old one and slide your synchronizer in the hole make sure all your marks line up then do the removal steps in reverse.

To replace the Sensor:(Do this if your computer throws a code (Check Engine Light) in reference to the Camshaft Position Sensor [CMP])

Locate the cam synchronizer there should be a small coolant hose above the harness disconnect the hose pull the spark plug wires from the coil move them out of your way lift up on the wiring harness shroud there are two 5.5 mm bolts holding the sensor to the synchronizer remove the bolts remove the sensor notate the position of the Hall effect sensor and install the new one in the same position as the old. Replace the 5.5mm bolts and bolt it in being careful not to overtighten. Plug back in the wiring harness and replace all displaced hoses and fasteners.

Warning: DO NOT USE the DORMAN Camshaft Syncronizer or Sensor.

The Dorman part has had numerous failures in other Tauruses. If the CMP fails in this engine, it will STOP the oil pump. This is dangerous as lack of lubrication will not be evident until the engine has seized. The Taurus does not have a low oil pressure light which would warn you to the event.

Fellow Members,

I installed 3 new Dorman(CHINESE) syncro units back the 2nd week of October (2) #689-104 (1996-1997 3.0L Vulcan) and (1) #689-107 (this was for a 98 3.0L Vulcan) . I put one in my brothers 97 GL, 1 in my mother-in-laws 97GL an the other into my mothers 98 SE.

The reason I went a head and changed these 3 is in a thread I made about my wifes GL.

Fast forward to last night, my brother said his car was leaking oil horribly. I checked it out and it was coming out of the sensor on top the new syncro. When I pulled the sensor off it was completely full of oil. I yanked the syncro unit out and I was totally Horrified. The roll pin in the gear was split in half and falling out of the gear and the gear was loose on the shaft....this is a press fit application(supposed to be). It also wore the thrust washer on top the gear. JUNKED! 2500 miles. I was fortunate it did not grenade his engine.

So I go pick up the mother-in-laws and pulled it out.....the gear was loose on that one and had play in it also...not totally failed yet but was already stressing the pin horribly and it has oil weeping under the sensor already. JUNK #2. around 1500 miles.

I then go pick up my mothers 98 and you guessed it...the freaking pin and gear are loose here also...JUNK.

These units WILL FAIL! I fortunately had all the old units lying on a shelf and put them back in till my Reman units(A1 Cardone...USA) come in Monday. The parts house was astonished but not surprised....loose tolerances and sub-standard metallargy.

Do yourself a favor if you are using one remove it and inspect it ASAP! I could understand finding a bad part out of a barrel but all three is a whole other ballgame.

BTW, Im going to pull the Reman-Napa(actually A1 Cardone) out of my wifes tomorrow to see how it looks. I BET it is perfectly fine.

Yours Truly,

Pro Ford

-Posted on the Taurus Car Club Forums

The A1 Cardone part has been used in multiple occasions and has not had the failures incurred due to the Dorman part.

See the "Related Link" below for a comprehensive, photo-illustrated conversation on replacing the camshaft synchronizer.

It has been discussed and generally accepted that the A1 Cardone part is a Motorcraft Refurbished unit that has been debadged.

Also see "Related Questions" below