I have an 05 FX4 with the 5.4. When the truck is warm I'm hearing a faint clunking noise coming from under the hood. I'm pretty deaf so it might not be that faint. Doesn't start right away, just when it warm's up. I thought it could be a loose connecter tapping on the firewall but when I turn the truck off it stops. I start it back up and the noise starts back up. I do have the Ford tick and that's not the noise. Does it in park and while driving.

I have no idea whats making this noise. happens about every 2-3 seconds. Do I have a pulley bearing going out? Am I going crazy?

I havent had the time or $$ to take it to the shop yet. I do still have warranty left but that's still $100 deductible.

Any ideas where to look? I've searched all the threads and havent found anything similar.

 

If you've still got warranty left I suggest taking it in and allowing the service advisor to listen. Its only $80 for a diagnosis, and an extra $20 to enact the warranty if they find something thats covered. As long as you've got the coverage use it!

 

It's raining today and my window gets stuck down. I've already had the switch replaced so I had to take it to the shop. Guess it's the swich again so I'll be on window swich #3 soon.

They told me the clunk/rattle noise is from the cats. They have some ordered so we'll see. I was starting to think that it was an engine clunk and that with my K&N CAI and my Edge EVO I had messed something up.

They also told me it would be about $80 to change the fuel filter. Looks like I'll have to price that out along with the tool to reassure myself that I'm going to do it.

Thanks for telling me to go to the shop, and thank you window switch for making me take it today. Dry would have been better especially at 38 degrees driving 15 miles to the shop.

 

Just an update for my old thread. New Cats did nothing to help the noise. Still have the knocking. Mechanic thought it was lower engine knock but it isnt. Now on a cold start I'm getting a loud clunk. Plus the TSB to fix the ashtray rattle didnt help and $40 down the drain.