Expedition has almost 100k miles on it. It's been solid since new, but after towing 7k trailer from Texas to Michigan this last time, she came back with a very unnerving and loud tapping sound. Maybe its a tap, or a tick, or whatever you want to call it, but its pretty loud. I can hear it best from the wheel well or from under the car near the rear of the engine when its running. I have a stethoscope and I can hear it pretty loud from the drivers rear (cyl 8) injector. It just sounds loud. I cannot hear anything wierd in the valve covers anywhere. I thought this was the cam phaser issue that everyone has, but I should be able to clearly hear that in the front of the valve cover, and I don't hear anything like it. I have had others listen to the car and they say its classic cam phaser tick, but why can't I hear that in the valve cover with a rodded stethoscope? Also, the thing is a freakin' PIG now. Even at 40mph, if you lay the pedal to the floor, it will barely have enough power to pass a vehicle in a reasonable amount of time. I am not interested in throwing cam phasers, chains, guides, and related items at it unless I can diagnose it.

There are no codes whatsoever using ForScan.

Is there anything else I can check? Any ideas? If I could hear the click or tap in the valve cover, that would clearly point me to cam phasers, but I can't.

Here's a video of the noise:

http://goo.gl/photos/ETwT9S9aNNLpkz9

 

Did any of the exhaust manifold studs break? If so you would hear an exhaust tick from that area.

 

Ill check. Its a mettalic tap rather than a air based pop, but I do want to make certain that its not exhaust related.

 

put your steathoscope directly on the coils

if the plug is backing out of the head you will hear it this way

this is how I keep track of the plugs in my 01 after I blew one of them out

if you get a loud rapping / hitting sound off the coil the plug below it is loose

- speaking of which it's been a year or more since I last checked .. I need to do it again soon

 

I changed the plugs, none were loose, and the sound did not change afterwards. The coils are all quiet. Thats a good check though.

 

I pulled the plug off the injectors I thought were bad. The noise does not change. Interestingly, the engine idle did not change either, in fact, it didn't seem to miss that injector being unplugged at all.

Anyway, that's neither here nor there. The noise is somewhere around teh valve cover in the driver side rear. I can hear it through the injector, I can hear it through the intake, and I can hear it a little in the valve cover itself. I cannot hear it clearly from the same spots on the passenger side. I also unplugged the VCT Solenoids on both sides, and there was no change in the noise or idle or anything.

 

No one has any insight?

Not sure I want to get into something that is unknown like this, maybe time to schedule an appt with Ford.

If its a failed lifter or roller follower, then that should be a pretty cheap fix. If its deeper or more involved, then I don't want to be involved with it torn apart on my drive anyhow.

 

 

Mine was a failed lifter. You just need to get the valve cover off. I was not comfortable with the procedure and tool needed to pop the lifter out and install a new one. The dealership did the work.

They replaced one lifter and the camshaft. The failed lifter chewed it up.

 

 

The lifter is bad.