Helpful thread, for squeak, squeal, chirp noise from V8 and OHV v6 engine compartment

[terry5732]

1998 Ranger. 4.0L.
Had this chirp, squeal, squeak on and off for weeks. It would never do it while I was wearing a stethoscope or even if I stepped out of the vehicle.

Mostly at lower RPMs. Sometimes sounded bearing, sometimes belt. The other day it was very noticable belt squealing at start-up. Then the CEL came on. Code showed camshaft position sensor. It was occasionally stumbling and missing on acceleration by now.

The culprit - a Mexican

The little magent was loose inside. Sometimes it would drag on the shaft below causing the chirp, dragging harder was a real squeal. The $25 Chinese replacement has the magnet enclosed within the plastic casting.

It is very tough to get at. The intake manifold hangs over it. I was able to replace without removing the manifold. Any shorter or fatter fingers and it wouldn't have been doable. Two wire bundles are significantly in the way. The two screws are 7/32". They turned easily. If hard turning- good luck. There isn't room for the socket after they come up just slightly. I was just barely able to see with a mirror, but not while working.

 

[SkeeterDon]

I too have the squeaking noise under the hood in my 99 x 5.0. Will remove belt as suggested and see if it remains.

 

[SCUBAnipper]

It could be your IAC Valve (Idle Air Control Valve) At idle when the motor is hot from sitting in traffic and it's a 100 degrees in the Florida Summer it sounds like a horn is going off under my hood, but when I go from idling in traffic or at a stop light it goes away. Turns out it was this little $40 2 bolt part. I hear these go bad after so many miles. I would look at that before tearing into the motor! Just my two cents.

 

[Turdle]

It could be your IAC Valve (Idle Air Control Valve) At idle when the motor is hot from sitting in traffic and it's a 100 degrees in the Florida Summer it sounds like a horn is going off under my hood, but when I go from idling in traffic or at a stop light it goes away. Turns out it was this little $40 2 bolt part. I hear these go bad after so many miles. I would look at that before tearing into the motor! Just my two cents.

true, but that noise is a wooo, we are talking about a squeak in this thread.

http://www.explorerforum.com/forums/showthread.php?t=191913&highlight=wooo

There ya go, we have you covered.

 

[SnTx4]

Just did mine yesterday. After all the threads on the synchronizer and how to's( Tdc, line the flag up, and any other concern, I was a. tad nervous about it. All I can say for anyone else wondering, what an easy job don't sweat it. It all makes sense when you get going and look at it. Btw, its nice not hearing that chirping/ squeal.

 

[richsaav89]

The problem I had with my explorer chirping was that my harmonic balancer had deterorated and was wobbling and chirping. Took me a long time to figure out until I had got a code (can't remember the exact code number) basically stating my crank position sensor had failed. When I got to replacing it I noticed marks on the balancer that matched the sensor magnets. After replacing both 2 months ago, no chirps and no engine codes. Runs smoother than ever. Just thought I'd throw that in.

 

[paullesho]

I found changing the oil with 4 quarts of good quality oil and one quart of marvel oil works wounders. Fixed my 4.0 that had a bad screeching noise at start up, even with the surp pulled. took a couple of hundred miles and two oil changes but, no more roller lifter or any other start up screech noise at all. bought it used with this problem cheep. I love to drive this one. Great vehicle! No wounder there is so many out there. Paul

 

[Keno Biebrich]

la verdad me encanto el tema de cmp, tengo una ranger 1997 4wd manual, y CEL encendido,la lectura que me da en el cpm test y la lectura entre pin 24 y 40 es de entre 5.3 y 8.6 Volts, quiero saber si esta bien o es correcto?

 

[Punjab]

Can anyone give me any insight into whether the chirping is caused by the sensor contacts rubbing or if its the actual bearings within the Synchronizer shaft?

I can get the sensor off of the unit currently installed in my truck but can't for the life of me get at the little bolt holding the retaining clip down to replace the entire unit.

If it's just the sensor unit I'll replace it with the reman one I purchased and button her back up. It would just really suck to put the manifold back on and tighten down only to find it was the bearings in the shaft all along.

Has anyone ever taken one of these apart to see what kind of bearing the shaft rides on?

Thanks in advance

 

[Punjab]

Also, can someone explain to me why you have to go through the process of syncing everything up without the tool? I understand if you were rebuilding the engine or something was moved while the part was out.
But if I can place the new part and it's rotating gear into the exact same location that the old sync and gear came out of shouldn't everything just pick up where it left off?

 

[Dave98XLT]

I have a 98 SOHC and it chirps briefly upon startup but is quiet after that.

Is this the same problem?

 

[austinmob]

Also, can someone explain to me why you have to go through the process of syncing everything up without the tool? I understand if you were rebuilding the engine or something was moved while the part was out.
But if I can place the new part and it's rotating gear into the exact same location that the old sync and gear came out of shouldn't everything just pick up where it left off?

You can do it without the tool but if the internal component (the bit that spins) is out by a even a fraction the timing of your engine will be out. Keep in mind when you remove the part it is connected to the engine by a gear. It wont come straight out it will turn slightly as it slides off the opposing gear to unmesh. it is an angled gear. When you put the new one in the same thing will happen. When you slide it into place it will mesh with the opposing gear and will turn. This is where you run the risk. I used the tool on mine and glad i did. I was not aware the part was going to turn on exit and entry to the engine. Woth tool in place, both pieces of the part spint together holding their exact position (as you see it installed) while it comes out. Using the tool is dead easy. 1. Place the tool on the part. 2. Turn the bottom pulley on the engine until the tool drops into place and fits snug. Then you have found TDC. Pull the old part out, fit the tool onto the new part and pop it back in. It doesent matter if it doesnt look as straight as when you took it out, so long as the tool holds the spinning part still. For example the whole part can face the opposite direction. It doesnt matter. Just make sure you get TDC.

On another note, TDC doesnt mean a particular cylinder has to be in a specific position for this excersise. It just guarantees the part is in a position relevant to the tool. The tool merely holds the two components of your part completry still so they remain in sync with each other.

 

[austinmob]

Can anyone give me any insight into whether the chirping is caused by the sensor contacts rubbing or if its the actual bearings within the Synchronizer shaft?

I can get the sensor off of the unit currently installed in my truck but can't for the life of me get at the little bolt holding the retaining clip down to replace the entire unit.

If it's just the sensor unit I'll replace it with the reman one I purchased and button her back up. It would just really suck to put the manifold back on and tighten down only to find it was the bearings in the shaft all along.

Has anyone ever taken one of these apart to see what kind of bearing the shaft rides on?

Thanks in advance

The Synchronizer is a 3 piece unit. 1. The sensor Cap. 2 the Body 3 the shaft.


The body and the shaft are not separetly serviceable as far as i know. The shaft spins inside the body. A lack of lubricant combined with moisture combined with other engine gunk gets up in there causing the noise. Someone did post on here that they were able to get a shot oil down the shaft with the unit still in place. That may be a short term solution but eventually you will have to replae the unit. Watch out for cheap chines parts. The sensor cap has a much smaller sensor magnet which i found caused my OHV to run a little heavier on fuel. I put the original ford sensor cap back onto my new part and found more power and better fuel economy.

 

[austinmob]

I have a 98 SOHC and it chirps briefly upon startup but is quiet after that.

Is this the same problem?

If all your belts are OK then it could be. Mine started with the same process isolated to colder months. Then over a 12 month period and a road trip from Sydney to Melbourne it started doing it even while driving.

 

[Kamaaina]

I was the guy who just took off the sensor cap, plugged the sensor screw holes and flooded the housing with oil and let it sit overnight (Posted 8/14/2011 Post #159). So far to this day there is no chirping on cold startup or anytime else. Motor runs super smooth and quiet. If you got the "chirps" why not give it a try....what've you got to lose? It's not that hard to do and I may make it a yearly maintenance item for me to take care of just to make sure it stays lubed.

 

[mlochala]

I just replaced the synchronizer in my 98 Mounty 5.0. My replacement unit from Autozone did not come with an alignment tool so before removing the old unit, I made careful note of the position of the rotating vane. As a matter of fact, I actually turned the crank slightly so that the edge of the vane was in perfect alignment with one of the slots in the top of the old unit. I snapped a few pictures with my camera just to be safe.

I must say I had a horribly tough time removing the old synchronizer. After removing the pinch bolt, I actually had to tap a pry bar along the base of it to get it to come loose. It took quite a bit of tapping (as well as asking forgiveness for a few choice words that got muttered) before it came loose.

Installing the new unit was also an exercise in patience. When lowering the new unit into the hole, I had to use a block of wood and hammer to bump the part into place. I also discovered that the vane would rotate about 20 degrees or so before coming to rest. So, after about 6 times of trial and error, I finally got it installed flush with the vane aligned with the noted reference mark.

After everything was put back together, I held my breath and turned the key. It immediately fired up and has been running very well since.

Thanks for posting this thread. It has been very helpful as a reference for this repair. When I first heard the chirping sound, my first thought was that it was an idler pulley. But then I remembered reading this thread last year and with the information I learned here was able to confirm that it was in fact the synchronizer instead of one of the pulleys.

 

[austinmob]

Well done. On a 96 OHV the part is located at the rear of the block near the fire wall. Theres bugger all room there and you cant see it to good either so the part is essential. That rotation of the vane is so the gear can mesh with the gear inside the engine. If you had the tool the whole thing would have turned 20 degrees and this would not be a problem as the the 2 pieces would still be aligned.

 

[va2001ss]

Great info in this post. I believe I have a bad camshaft syncro on my 99 4.0 OHV. Will I have to remove the upper intake to get to it?

 

[Abbondanza]

I have to vote yes on that one, maybe even the lower, given where it is on my 96 OHV 4.0. I should have done it when I replaced my heads, but of course it wasn't chirping then...it only chirped this winter on cold starts below 40 degrees F, so I'm going to change mine out in the fall at the first sound of chirping to nip it in the bud:

 

[ncz]

Man, great thread! Guys, just to be sure, if I remove the sensor cap only and replace the new one exactly, I should be GTG, correct. That's what I get from reading just want to make sure before I pop it off and look. I am afraid its the synchro but I think I am ok with replacing that also after reading this thread. Thanks again!!