bird chirp -- water pump?

[Jellysick]

I have a chirping as well, however the sound from my truck is a consistant 12 seconds apart, no matter the speed or RPMs. I think its only on when the A/C is on too, so that would obviously pin-point the problem. I had ford look into it when it was under the factory warranty, and they supposedly replace the blower motor (??) twice... chirping still there though. Its got to be the a/c!

Good luck finding your chirp, its annoying as hell, but I just crank the radio so I cant hear it!

 

[bajadog]

Rhett,

Is the sound only occuring when the vehicle starts up cold, then goes away
after it warms up?

 

[Rhett]

Rhett,

Is the sound only occuring when the vehicle starts up cold, then goes away
after it warms up?

It does *not* occur when the vehicle is first starting, or even a few minutes into the drive. It only occurs 10 minutes into a drive, when it's under 50 degF, and then it stops within a few minutes or so...after that, it's perfectly quiet.

 

[Runnin'OnEmpty]

Rhett, as you mentioned in the other CMP thread, there's a good possibility it's the CMP chirping. I've read lots of posts on them making noise, and since you've changed or checked everything else......

 

[Rhett]

What mechanical feature is inside this sensor that would cause this chirping? I thought the sensor had no moving parts in it... ??

 

[bajadog]

I changed my '97 4.0L SOHC serpentine belt to a Goodyear gatorback, and
a goodyear tensioner & idler pulley.

That fixed my cold bird squeak.

I bought all those parts on Kragen online for $73.50.

http://www.partsamerica.com/Default.aspx

 

[Rhett]

I tried 3 different belts. They did not affect the bird chirp at all.
I'm presently running a Goodyear Gatorback also.

I'm looking at the crank sensor (aka CKP, CMP sensor) right now, but my question still stands, what moving parts does it have that could cause a bird chirp?

 

[Creager]

no moving parts, leave it alone

are you sure your bird chrip is comming from the belt-train?

Take your sethascope and check undeneith the car, maybe its comming from the bell-housing area?

 

[Turdle]

ok rhett
Take the serpentine off, leave it off till morning, start vehicle and see if chirp is there. if it is you have eliminated everything up front, and it is the cmp(cam position sensor) shaft. It is a mechanical revolving device. If you want, here is a link of a bad one I helped replace off a v-8

http://media.putfile.com/squeaky-camsaft-position-sensor

 

[Rhett]

ok rhett
Take the serpentine off, leave it off till morning, start vehicle and see if chirp is there.

That's just it--I have run it without the belt for a short time. It was quiet with or without the belt. I have to drive the truck for 10 minutes on a cold day before the chirp appears. I'm not sure if I want to drive it 10 minutes without a belt. I've seen enough cracked heads on these trucks...

I'm still doing research on the CMP sens. I am not sure if the 1st gen sensor is the same as your 2nd gen one. Mine looked like a simple tone-ring type sensor that simply measures the magnetic fields given off by the grooves in the crank pulley. I'll do more research when I get the time (which is not lately) and will advise...

 

[Runnin'OnEmpty]

Rhett, that sensor at the crank pulley is the crankshaft position sensor. The one at the back of the engine (hidden by the intake) is the camshaft position sensor. The camshaft position sensor is the one that squeaks, and I'm thinking more and more that's where your chirp is coming from. It seems to be very common with our Explorers.

 

[94explorer2x4]

R O E is right cam position sensor replace it and it will be fixed after reading the thread I can almost promise you it will be fixed, have you noticed the speed of the chirp? if you take noti it probably squeeks 1 every 2 rotations of the crank wich would tell me cam sensor because the cam is running at half speed of the crank. depending what style of crank sensor you have it might be possible to take the cap off the sensor and spray wd-40 in it to test it.
Nate

 

[Rhett]

Rhett, that sensor at the crank pulley is the crankshaft position sensor. The one at the back of the engine (hidden by the intake) is the camshaft position sensor. The camshaft position sensor is the one that squeaks, and I'm thinking more and more that's where your chirp is coming from. It seems to be very common with our Explorers.

Ah ha Thanks for the clarification about the crank vs. cam sensor. I do think that you are on to something...

I've never had to mess with a cam sensor back there. I assume that I can simply remove the upper intake manifold to allow myself good access to the cam sensor. I hope it's not expensive, if I do have to replace it.

 

[performancenut]

Might want to check your cam position sensor. These are known to develop a squeek.

x

 

[Turdle]

When you are pricing the part, there will be some confusion. What you need is called a synch drive unit I believe.
It may be worded cam sych drive, or cam sensor drive, or cmp drive.
You don't need a new sensor though, most likely. The sensor itself is resident(screws onto) on the sensor drive shaft unit.
There, are you confused yet?

 

[Rhett]

R O E is right cam position sensor replace it and it will be fixed after reading the thread I can almost promise you it will be fixed, have you noticed the speed of the chirp? if you take noti it probably squeeks 1 every 2 rotations of the crank wich would tell me cam sensor because the cam is running at half speed of the crank.

Yes Nate that is about right, I think you all are on to it, but we'll see.

I can see it squeeking once of every 2 rotations. It is quite rpm dependant. When it does it, Under 1000 rpm it's quiet, 1000+ rpm the frequency of the chirping increases with rpm.

Creager said to listen around the bellhousing...that was a good suggestion too...same area we're talking about.

I'll look at it this weekend and spray it with WD-40 or lith grease and see what that does. If I can get at it without removing the upper intake that would be better yet.

 

[Rhett]

There, are you confused yet?

heh. Yep.

I appreciate the help. Maybe if this turns out to be the problem, this thread can help others in the future.

 

[SVO42]

I have similar problems with my Ex. Just because it's squeaking does that mean there's actually a problem with the sensor? I can live with the squeaking, but I don't want to be running with a bad sensor.

 

[Creager]

Hey Rhett, i just looked at the Cam position sensor on my block, that i have bolted to the stand. It looks like where a distributor would go, its like where they used to put them on the older 2.9's or something. oo, that gave me an interesting idea for a carbed 4.0, hehehe.

You shouldnt need to remove the lower intake, but im sure it would make things easier. The lower intake is kinda 'knotched' around that area. You will see what i mean

Oh by the way, Rhett, i got my upper intake hot-bathed for $20 at the machine shop im getting a lot of work done. Prestine! that thing is CLEAN. $20 well spent IMO

 

[Wrench]

CMP snychronizer base unit

The reason for the bird chirp noise emitting from the drive unit (not the sensor itself) is lack of lubrication on the upper shaft support within the drive unit. When you remove the worn out CMP synchronizer drive unit you will notice the excessive side movement on the upper shaft. If you were to continue to drive your vehicle with the old drive unit you would end up dead in the water at some point as the upper shaft cam would destroy the CMP sensor. The only reliable fix is to replace the synchronizer drive unit. Make sure you understand how to remove and install the drive unit properly before you start the process. Make sure you purchase the right drive unit and alignment tool for your particular year, model, and VIN. Also look cafefully at the interior of the CMP sensor to make sure it is still serviceable.