I looked around and did see that anyone had this issue before, so if this is a duplicate I apologize.

My 07 F150 5.4 V8 flex had a temporary issue that worries me. I was towing a trailer (though I don't know I doubt that had anything to do with it), and suddenly I had a bad shake, and what i would describe as a "knocking" for lack of better description. It basically sounded like a diesel engine all the sudden. The problem continued even as I stopped and put the truck in park. Fearing a major problem I shut it off, and a couple minutes later after inspecting the engine compartment I started it again and it ran as if nothing was ever wrong. I've been driving it all day and have not been able to duplicate the problem. Has anyone ran into a similar issue or know a likely cause? Thank you!

 

I have had this issue too. Just driving came to a Ted light and all of a sudden everything started shacking rpms were fine everything looked fine. It's happened a few times to me and still unsure what the issue is.

 

Try looking at the fuel pump driver module.

 

Could be a number of things. First things first, did it throw a check engine light? If so, the truck needs to be scanned for stored codes that will point you in the right direction. My first thought was a coil pack issue, but could be an oil starvation problem with the cam phasers, which will cause the diesel sound (probably should read up on that anyway as it is widespread).

 

No check engine light came on and oil seems to be fine. Do you think it could be caused by leveling kit?

 

No, a leveling kit has nothing to do with the engine.

 

No check engine light or stored codes. It did it again today. Both times it occurred when slowing to an idle, and both times it corrected itself by turning off the engine and starting it again. I'm thinking possibly a timing issue?

 

Has that problem with my truck. It was a brake booster vacuum line which has a recall. Check it out. Good luck

 

I appreciate all the help guys! I finally reproduced the problem and pushed it until I got a code. The code it gave was P0340 which is left bank camshaft sensor malfunction (P0345 is right bank). I went ahead and changed them both, and about $35 later all is well. This was a very easy fix that anyone could handle. All you need is an 8mm socket. Wish it wouldn't have gotten so bad before it threw an error code. I would have had this squared away weeks ago. Thanks for the help guys!