First off, my truck has always ran awesome. Great power, smooth shifts etc. Bought it used, and from day one it has always had this engine rattle. Happens when going up hills and sometimes on the highway. Sounds like marbles in a tin can. On the original plugs, it would
start at 2500 rpm. Changed them to autolite platinums and the rattle would start at 2000rpm.
Some of ya'll on here recommend to go with motorcraft double platinums. So today I took the autolites out, and installed Motorcraft sp440's. Well I just took it on a drive, and now the rattle starts at 1700rpm and ends at 2000rpm! Its almost completley gone in the 2k range, where the rattle used to be loudest.
Any suggestions on how to troubleshoot this noise? I could always turn on music and ignore it, but if the rattle is causing damage to my engine, I'd like to get it fixed. The gaps are correct, and I love the way the truck runs and idles, SO i'm not changing these plugs again. I also find it kind of weird that the noise goes to a different rpm everytime I change the plugs.

PS When I fill up with a better octane gas, the noise lessens significantly....

 

could be a timing chain tensioner problem

 

Thats what I thought at first as well. When I first heard it, I was like "Oh great now i need a new engine, thats why I got a good price on it...." That was 30k miles ago. But my truck is an 2004 and i read that Ford fixed this problem after 2002. Also would the timing chain quit rattling when I put in a better octane of gas?? I filled it up with mid grade the other day, and the rattle was almost completley gone. I just figured it was something to do with ignition since it responded to the changing of spark plugs and the better gas.

 

yea youre right...get some fuel injector cleaner(lucas is some good ****) and run that through and see if the problem still exists

 

Nice I'll give that a shot. I seafoamed it the other day before I changed the plugs and it smoked but didn't do anything for the rattle. I'll give the lucas injector cleaner a try, hopefully that works ...Thanks

 

Try cleaning the throttle body with some seafoam deep creep spray. Clean the butterfly flap really good. That should get rid of it.

 

Well I just cleaned the maf to see if that would solve the problem. My idle is now smooth as butter. But the engine rattle is still there...I cleaned the throttle body last year when i was inspecting the cable, and got all that nasty black junk off of it. SO the only thing left I guess is to try fuel injector treatment. If I run seafoam through the fuel tank, will that work as well as the Lucas brand cleaner? Any one ever try "Gumout"? my Walmart has it for like $2
I could also try changing the spark plug wires as well. I have some autolites on there now, would it make any difference if I switched to motorcraft oem w6120? I've always heard that spark plug wires are all basically the same, as long as they are a quality brand. but who knows....

 

I have used the Gum OUt. It works good. Grt the total fuel system cleaner.

 

liquid cleaners get so dilluted and dispersed its hard to get them to "clean" anything. An unjustified rattle will not just appear one day from excess carbon..its a mechanical failure. sorry I am of no help as to what but its not just something a little seafoam can delete...help yeah but not delete

 

Any input is helpful. From what i've read, spark knock can be the result of several minor problems, which can lead to preignition. I hope to keep chipping away at this until I solve it. If not I've got a good metal collection that can be applied when needed.
I also agree with the thought that a simple bottle of snake oil won't fix my problem. But to read some of these reviews on seafoam, you'd think it would solve about anything. I've read pages of reports with people saying it has cured all their engine issues, so i figured I'd give it a try.

But after fuel injector cleaner and new wires, IDK really what else to try! I hate to keep throwing money at my truck, if its not gonna do ****.

I also checked my heat shield on the cat, and its not loose and rattling or anything. Is there another heat shield somewhere that could be vibrating around?

Also, does anybody have any theories on why the pinging keeps changed the rpm range eveytime I put different plugs in? Its now gone between the 2000 and 2500 rpm range where it used to be loudest. Now its between 1500 and 2000 with the motorcraft plugs. Just curious on the reason why...

 

Going back to DJ's answer this could be the timing chain rattle.