Explorer chirping

[major]

I see there is another similar post but didnt want to hijack his post so im starting a new thread. Here is my issue:

I have a 98 v8 4 door explorer and have a chirp coming from the engine compartment. Ive tried replacing all the easy parts (tensioner, top idler pully, and the belt) with no luck. I also changed the alternator not a year ago. The sound will come and go but seems to be getting more frequent. For a while it would chirp a few times then stop then start back.

Can anyone give me a dummies version of how i can try to diagnose this myself? I saw where someone on the other thread said to use a length of hose to listen with. I havent tried that yet but did try my screwdriver on the componets with no real luck. I soppose the hose will be more directed than just listening. Does that sound about right?

Are there any particular sounds each componet would make?

Thanks and im open to any help so please post anything you feel may be useful.

Major

 

[steventadams]

a chirp could be from the cam position sensor...

 

[major]

The sound is kind of what you would expect with a belt slipping but it isnt. for lack of a better example its an eekk eekk sound. I dont know enough about the engine to say much on this but how would the sensor make a sound? Is it a mechanical sensor? I dont mean that in a bad way its just another question i dont have an answer to.

Major

 

[steventadams]

You can learn more about the cam position sensor here: http://www.explorerforum.com/forums/showthread.php?t=207905&highlight=cam+position+sensor

Does it sound like this: http://www.explorerforum.com/forums/showthread.php?t=197319&highlight=squeak

But the best way to diagnose is to take the belt you replaced back off and run the engine for a few seconds (not too long though because the water pump wont be driven). If the squeak goes away you are probably looking at a bearing going bad in one of the pulleys driven by the belt. If the squeak persists, you know its not a pulley because they aren't spinning and the noise is still there.

If it doesn't squeak with the belt off, turn the engine off again and spin all the pulleys by hand and try to find one that isn't turning well. That's the one you want to look into and inspect.

 

[major]

Thanks for the heads up on that. Ill pull the belt tomorrow and see if i hear anything.

I spun the pullys when i changed the belt and the top ones didnt feel like they had an issue but i didnt check the bottom idler pulley now that i think about it. Running it for a minute with the belt off will atleast tell me if its the cam position sensor or not though. Ill recheck ALL the pullys while the belts off.

Major

 

[steventadams]

Keep us posted

 

[Turdle]

http://www.explorerforum.com/forums/showthread.php?t=161590&highlight=bird+chirp

 

[major]

I know its been a while but im looking at the issue again and after checking it with a short length of hose i bought it sounds like its either the water pump or the Cam position sensor. If i had to choose i would say the cam position sensor as yall noted. The sound is sharper there when i get the tube sitting on the sensor vs on top of the water pump.

Ive read some of the threads on replacing the sensor on a v6 and it seems allot harder on that since its on the rear of the engine. Since mine is a v8 and pretty accessable how hard is it for a novice do it yourselfer. Changing bolt ons like shocks, alternator, ideler pull and tensioner wernt hard. Is there a good writeup on changing one on a V8? Also what auto part store brands are good to go with? We have auto zone, Advance, pepboys and Oriley here.

I see that there are two bolts that look like they hold the sensor on so that would be great if it was just a drop in change. My luck ushually isnt that good though.

Another thing is, if it is that part would it be the core withe the gear on it or just the sensor? Do i need the tool if its just the top portion with the plug on it or can i just drop the new part on and run with it? If not ive seen where i need to find top dead center on the "compression" stroak. Is there any easy way to do this without removing allot of parts? I live in an apt so i cant break this down in the parking lot. Whats the best method to move it to TDC?

Let me know what yall think. In the mean time ill do some more thread searches. Sorry for all the questions im just tring to get everything covered. I also want to add that i dont get any engine codes and the chirp comes and goes.

Major

 

[xlr8r2008]

If it is the Cam Synch

My chirping was exactly as you described. I diagnosed it by removing the belt and eliminating the belt-driven accessories. The chirp was still there, so I removed the two small bolts that hold the Cam Positioning Sensor and inspected the sensor - it was not destroyed as many have reported, but I didn't expect it to be since I was not getting a CEL. I sprayed a fair amount of WD40 into the (now open) top of the Cam Synchronizer, replaced the Sensor and belt and restarted the car - no noise. So now I know it is the entire Cam Synchronizer and I have one on order from O'Rielly. I had priced a reman Cam Synch at around $125 (less core) from Auto Zone and was surprised when O'Rielly quoted it at $43. So it pays to check around. Also, make sure you get a replacement Synch with an alignment tool to make sure you set the new one correctly. Here is a link to a site that describes the complete Cam Synchronizer replacement procedure:

http://autorepair.about.com/library/a/1h/bl025h.htm