Squeak at 3000rpms - CMP Synch Drive?

I was driving along and everything was normal until I heard a squeaking sound for 1-2 seconds. At first, I thought it was from the suspension or that possibly something in my cargo bay had shifted. A mile or so later, I heard it again. I listened carefully for the next several miles and the sound was intermittent. However, I noticed that it only occurred between 2800-3200rpms. Driving along at 40-45mph, I manually shifted out of drive and into 2nd gear and increased my speed until the rpms were around 4500. I then let off the gas and shifted back into drive and as my rpms crossed through the 3000 range, the squeak could be heard again. When I arrived home, I left the X running and popped the hood. There were no abnormal noises while at idle. I shut it off and checked the pulleys and they all seem to be fine. My grandfather asked what I was doing, so we took a short drive so he could hear the noise. He said he thought it was coming from the rear passenger area, but from the driver's seat, it sounds like it is definitely coming from the engine bay. Another notable incident occurred on this drive. In effort to reproduce the sound for him, I shifted into 2nd just as I noted above. The sound did, indeed, reappear, but for whatever reason, when I tried to increase the throttle, the engine wouldn't rev at all for about 2 seconds. It was like my pedal was dead. I shifted back into drive and the throttle worked again. Could this be related?

Could this be the infamous CMP Synch Drive failue? I read through the CMP threads before posting and it seems that most people heard the chirping upon startup. I can only hear it around the above mentioned rpms. Also, I think the best way to describe the sound I'm hearing would be that of a shopping cart that has a wheel that gets stuck every few revolutions. Its not a high pitched sound like the one in the CMP video, but it's not a low pitched whooshing sound like that of a wheel bearing either.

Bump


If this is, indeed, the CMP synch drive, would it be OK to keep driving the Explorer for a week or so until I get a chance to take care of it?

A failing CMP drive will sound almost exactly like a bad idler pulley bearing. It will be a high pitched chirp. Every bad CMP drive I've run across will make the noise at various RMP's, but you don't need to drive the vehicle to get it to make the noise, it will do it without any load on the engine. Your description sounds more like something that is related to engine load and while it could be the CMP drive, I have never run across one that only made noise under load.

Thanks for the insight, MrBoyle.

I've been pretty sick this week, so I haven't been able to do much in the way of tracking this sound until today. However, a few days ago, I did grab my camera and shoot a short video of the noise. I was in the EF chat later that night and a few of the members indicated that it sounds like a bad idler, tensioner, or possibly even the alternator because my voltmeter seemed a little low. Today, armed with that information, I first tested the voltage at the battery both while the vehicle was off and then on. Those numbers are 12.35 and 14.65 respectively. The alternator seems to be doing its job. Next, I removed the serpentine belt to see if all of the pullies spun freely. They did. I then started the vehicle and let it idle for a minute or two because the sound doesn't seem to be as audible until the vehicle has started to warm up ever so slightly. With the belt removed, the sound is still present in the same 2800-3200rpm range.

Here's the video from the other day.

I guess I misunderstood your first discription. If its happening w/o the belt and w/o a load like in your video, my first guess would be the CMP drive.

Am I crazy, or is a "Camshaft Synchronizer" and a "Crankshaft Angle Sensor" the same thing?

RockAuto.com has the following listings:

Camshaft Synchronizer:
DORMAN Part # 689101 (Includes Allignment Tool) $40.79


Crankshaft Angle Sensor:
A-1 CARDONE Part # 30S2800 (w/ Step on Plug) $49.79+$40.00 Core
A-1 CARDONE Part # 30S2800L (w/o Step on Plug) $49.79+$40.00 Core

wrong photo

It looks like RockAuto used the camshaft sensor photo for the crankshaft sensor. The crankshaft sensor tells the PCM when the position of the #1 piston and doesn't look anything like the photo. Its located adjacent to the crankshaft damper/pulley.

The first pic and discription is the part you want.

Now I just need to figure out who carries the Cardone part as opposed to the Dorman unless the Dormans are no longer junk.

I've been doing a ton of reading and it seems that the Cardone units are also now made in China and are junk just as the Dormans are. Does anyone have the Motorcraft part number for the camshaft synchronizer? The local stealership has the Motorcraft unit for $153.36, but I'd like to see if I can find it online. I'll also need to buy the allignment tool as well, which is $30-$40. I can see now why people find the $45 price tag on the Dorman, which includes the allignment tool, so attractive.

On a side note, I noticed that RockAuto has the Motorcraft unit for those of you with '96-'97 5.0s. Us '98-'01 guys aren't as fortunate.

After further reading, I've discovered that as long as the A1 Cardone unit is a remanufactured unit, then it should be fine as they use Motorcraft cores and grind off the part numbers when remaning the parts. Only the new production units are inferior Chinese parts like the Dormans.

With that being said, I called Autozone this morning and they couldn't find a "Camshaft Synchronizer" in their system. He said they do have "Crankshaft Angle Sensors". I told him I didn't think that was what I needed. I then stopped by the local Napa and the salesman also referred to the part as the "crankshaft angle sensor". I asked if he was looking up the correct part and he spun the monitor around and the name was displayed as "Crankshaft Angle Sensor/Camshaft Synchronizer". He pulled the Dorman unit that he had in stock so I could visually identify whether or not it was the correct part and it was. He said he could special order the A1 Cardone reman, but it would be more than a week before it would arrive.

It appears like the parts are, indeed, the same thing, but for whatever reason, they go by two different names. Should I take a chance and order the A1 Cardone from RockAuto even though it is listed as a "Crankshaft Angle Sensor"?

I'm so confused. I listened to some camshaft syncrhonizer videos on Youtube and my noise sounds nothing like them. The NAPA guy said I could return the Dorman unit if I'm not satisfied with it. I haven't bought it yet, but maybe I should just to see if it eliminates the sound. If it does, I'll order the Motorcraft part for final replacement and either return the Dorman or put it on ebay. I'd feel kind of bad returning it after I've already bolted it to the vehicle... even if it's only for a couple of minutes.

I ordered the camshaft synchronizer last week and received my shipment yesterday, but the place sent the wrong part. With that being said, I decided that I needed to at least get started today. Since I knew I would be pulling the plugs to find TDC, I picked up a can of Seafoam and some new plugs. My plan was to Seafoam, pull the old plugs, rotate the crank until the allignment tool fits on the synchronizer, and then install the new plugs and let the X set until the new synchronizer comes in. If all would have went according to plan, I could just stick the allignment tool on the new synchronizer, slip it into place, and bolt everything back up. Unfortunately, I made it to the part where I needed to rotate the crank and for the life of me, I can't get it to budge. All of the spark plugs are out and I can't move it. At first, I tried prying in one of the holes on the power steering pulley as I had read in another post. This worked for about 1/4 turn, but then the belt just started slipping on the pulley. I thought the crankshaft was supposed to be relatively easy to turn once all of the plugs are out, but that's not the case. Am I forgetting something?

Any tips?

Get a socket and ratchet and turn the crank by the center bolt on the harmonic ballancer. Yea, its hard to get to, but that is the best place to do it from.

Any idea of where I can find what size the nut is? I'm not sure if I have a socket large enough, so I might need to buy one before I give it another shot.

Removing the serpentine belt will help a little. Taking the fan and shroud off will really make turning the crankshaft a breeze.

I tried turning it both before and after taking belt off, but I was trying to turn it by hand thinking that there would be little resistance. I'll give it another go with a breaker bar. I wish it wasn't so cold and nasty outside. Times like this make me really want a garage... as if I don't want one all the time anyway, lol.

I tackled the crank rotation today with much success. For inquiring minds, it required a 15/16" socket. With a 1/2" drive ratchet and a 1" (yes, that is 1-inch) extension, I was able to rotate the crank with ease without removing the fan shroud. Once the allignment tool fit onto the synch drive, I installed the new plugs so I could keep moisture out of the cylinders. The new synch drive should arrive tomorrow. The coil packs are out of the way, so hopefully the rest of the install will go with ease.

Does anyone know if the old synch drive can be removed without completely removing the coil pack bracket? I removed the coils from the bracket and it looks like I'll be able to pull the synch drive out through one of the two holes in the coil pack bracket and install in the opposite order.

I arrived home this evening (technically yesterday evening since it's 1am now) and the new camshaft synchronizer had arrived. I thought I would snap a few pics of the Dorman and the Motorcraft. Look carefully at the closeups of the pins in the shaft. You can see that the Motorcraft pins are thicker. The Dorman also has some side-to-side play in the shaft.

I came home from class yesterday and the rest of the install went great. The X is now screech free. I would have posted last night, but our power was out due to a huge wind storm. I'm posting this from school.