Hi Everyone,

2000 XLT SuperCab 5.4L with 221,XXX miles

On my way to work this morning I noticed that I suddenly had a loud tapping noise that goes along with my RPM's. Engine runs fine otherwise though. When I got home I removed the belt to rule out any of the accessories and checked to see if my spark plugs were coming loose. All plugs on the side making the noise are tight, so it's not a plug working it's way out.

Sounds like the noise is coming from underneath the valve cover but its hard to pinpoint. May be coming from lower in the engine, but I hope not.

Here is a short video of start up while warm: https://www.dropbox.com/s/5wmfszg68c...33709.mp4?dl=0

From googling it sounds like I may have spun a bearing but I wanted to get some other opinions/ideas before I go any further.

Thanks,

- Erik

 

Remove one fuel injector connection at a time. Usually if its a rod when the injector is disconnected on the cyl that is generating the noise the noise will diminish or stop. If this works then its usually a bad rod bearing. Make sure the fan is not hitting a plastic harness connector that migrated to close to the blades..I have seen it happen several times and sounds just like a rod knock. Use a stethoscope as well to determine the exact location of the knock. A chain tensioner could also be the source of a knock so listen directly behind the front cover with the stethoscope... I have also seen the oil baffle that is under the cam cover come loose and drop onto the valve train and start bouncing from the cam follower creating a knock noise.

 

Sounds to me like its the valve train. After trying to locate the noise as indicated in the previous post, I think I would remove the valve cover and take a look.

A compression test may also tell you something.

 

Dynotech/Roadie,

I went and bought a stethoscope to pinpoint the sound and it was directly in the middle of the valve cover. I opened it up and I found exactly what Dynotech described in his last suggestion. The oil baffle for the PCV had fallen off of the valve cover and was bouncing on the cam. No damage from what I can see since the baffle was made of plastic. So I ordered a replacement valve cover.

Thanks for the suggestions guys. I'm happy it worked out to be so simple.

- Erik

 

Congratulations on finding the problem and I'm happy it wasn't more serious!!

 

Good job. Glad you found the problem. Those are glued on with epoxy but over the years I have found maybe a half dozen or so that have come loose making a knocking noise. I know people laugh when I suggest the fan hitting a wire harness connection. However Several times Ford flew me to a body and assembly plant to find a knock noise concern on vehicles coming off the assembly line only to get there and find a plastic harness connector being slapped by the fan making a perfect knocking noise. I have no doubt that many engines have been pulled because no one looked for that possibility and the techs determined that the engine was bad pulling the engine...always expect the unexpected and don't rule anything out when searching for the source of a noise. Take care.

 

Great info dynotech thanks for sharing!

 

Just one more thing regarding the cam cover oil baffle then I will shut up and move on.
I suspect some people that may find that baffle loose will just discard it and reinstall the cam cover less the baffle. The reason that baffle is shielding the PCV is because they found that while the engine is operating the oil squirting out of the lash adjusters just below the PCV valve were actually shooting oil directly into the PCV valve. This condition caused excessive oil consumption in the engine. So by installing the baffle the oil was redirected and could no longer enter the PCV valve.

 

No need to "shut up and move on." You're sharing valuable information that comes from experience which helps me and may help someone in the future. No problem with that here.

I figured thats what the baffle was for since it was covering the PCV. This may also explain why I have had a slightly excessive consumption of oil for a little while now. Maybe it was leaking past the failing epoxy for the baffle? Either way I have a new valve cover I will be installing today.

Thanks again,

- Erik

 

Your very lucky. My buddy lost his 5.4 3v engine last week in his 07 King Ranch F-150 with only 99K on the odometer. Its hit or miss with these motors.

 

The OP doesn't have a 3v.