Hi All,

I was just wondering if anyone has every notice a distinctive engine rattle at about 1600 rpm. It is strange, doesn't seem to happen in any range except between 1600-1800. Doesn't impact performance at all and really is not that annoying but is something I noticed and want to ensure I can a jump on it if it is anything I should be concerned with. One side note is that I have a K&N FIPK installed as well.

Thanks

 

No replys yet?

We need more info.......what are you driving, any mods(including tire size change), etc.

Dan

 

um. try crawling under the truck and have someone hold the rpm at 1600 for you. my guess is that it is comming from either the muffler or one of the cats. ive had this happen before where a cat rattled only at a certain rpm. has to do with the frequency that causes resonance and blah blah blah, not gonna talk about physics.

 

Sorry, my sig is now included

 

I have a similar rattle.........not sure if it's the engine or not. Mine's beteween 16-19 (oo) rpm, and sounds like it's coming from the front drivers side . It's going in for a new seal on the tranny (where the drive shaft comes out) next week sometime........I'll get them to take a listen...........


Anyidea's folks?


Fyi: mines the same as cyclone's truck, execpt a 99.

 

I forgot to ask for your total miles.......but here is my guess. You may have a dirty/clogged EGR valve and/or port. This might lean out the a/f mixture, causing a lean condition???

Before doing anything though, I'd try running with the stock air filter installed. I don't really think the K&N is doing it but the eng. might be running a little lean at those rpms. Btw, I never use the stock paper air filter but it's worth trying the stock one.

Dan

 

I have a 2001 F-150 XLT 5.4L. I have had it in the shop quite a few times for the various noises I hear coming from the engine compartment, or so I believe that is where it's coming from. Anyway, the dealer keeps giving me the run around. First and second time in they could not duplicate, I finally took them out with me and was able to duplicate with technician present. They took in the shop and checked EGR system, for exhaust leak but they were unable to pinpoint the problem but assured me was not an issue, my thought was "not an issue, it's a 32k dollar truck- it most certainly is an issue". I then changed dealers due to lack of knowledge at first dealer. The new dealer first said YES Ford is aware of this and has their engineers working on it- result " this noise is normal for the 5.4L engine". This dealer repaired a few other minor issues I had so I thought I'll give them one more shot too. Took their technician with me on road test we heard two distinct noises- one that sounded more like a rattle and it was easily heard, this we believe, after further investigation is a resonating catylitic converter (this is the noise that comes and goes at will), the second noise is very faint and this is the one I believe to be coming from the engine and only is noticeable at light to medium throttle not heavy due to overwhelming engine. i love this truck but the more I read hear the more scared I get.

 

Thanks to all for the replies. I started out by taking JA4x4's advice and climbing under the truck. It appears as if the rattling I am hearing is coming from the cat. There is a distinctive sound that occcurs between 1600-1800 rpm.... Unless is gets worse I am not going to worry about it too much. I just wanted to ensure it wasn't something wrong with the engine.

 

dont just look and listen. Grab a stethoscope and actually put it on the various engine parts until you find the exact part.

I though mine was an exhuast rattle at 1100 to 1200 rpm, but was actually the alternator of all things.

So the lesson is, don't assume.

 

I know that most have pointed you to the cats and like I said before that is where I believe the one rattle comes from. In my first posted reply I mentioned that I had the rattle you described however I also have the other engine noise that is much fainter and is only observed under light to medium throttle. Has anyone here heard this noise? If not I'm happy for you, can you direct me to the appropriate post where someone else may be able to help me. I think that J-150 is right I have not used a stethoscope to verify it is definitely coming from the cat's.

 

I have the same rattle under a little rpm in drive... I am of the mind that it is the Cat. Converter Heat shield though and am not too worried about it; although it is a little annoying with the window down. I also noticed that passengers can not hear it even with the windows down... Of course the Flowmasters can attribute to that too...

I am just more in tune with my truck than my passengers...

 

My 4.2 v6 does the exact same thing, although I thought it was just pinging due to 87 low octane fuel. Try some premium fuel and see if that helps?