What do you think about this?

[kingmidaz]

It seems to happen on colder days than warm, but when accelerating I hear a rattling noise almost like the sound of a rollercoaster chain towing a car but not nearly as loud...car doesnt have a check engine code or seem to lose performance drives great. The noise stops of course when I take my foot off of the pedal. I have a 2002 LS 3.9.

 

[kwazy]

check under the car for any heat sheilds

 

[kingmidaz]

ok but it sounds like its coming from UNDER the hood...sounds like cans being drug behind me ...if that makes sense

 

[gcwimmer]

You are using 91 grade gas?

 

[kwazy]

not sure then

 

[kingmidaz]

You are using 91 grade gas?

hell no always 93 even when they had the "shortage" but it "may contain 10% ethernol"

 

[97stscaddy]

How many miles? When was your last oil change?

 

[LsUnV2]

have u looked under the hood. m:shifty:

 

[02LincLS]

misfire or catylitic converters broken inside?

 

[Right on the Mark]

Better hope its not a timing chain issue. The V8's have all kinda problems with chains and tensioners.

 

[kingmidaz]

How many miles? When was your last oil change?

103,126 I change my oil every 4-5k....I use high performance 5-20 weight...not loud enough to be a valve rattle though

 

[kingmidaz]

have u looked under the hood. m:shifty:

lol.....of course man....thats why I'm asking you guys because I've checked it out

 

[kingmidaz]

misfire or catylitic converters broken inside?

humm would think that would cause the engine light to come on ....no? also would a misfire give other symptoms in addition to that? maybe a loss of power right? because the car runs great no problem accelerating or anything like that

 

[kingmidaz]

Better hope its not a timing chain issue. The V8's have all kinda problems with chains and tensioners.

I'm going to check that in the morning...thanks for the heads up...I'll keep you updated if you care...

 

[kingmidaz]

You are using 91 grade gas?

no 93

 

[605RezlifeLS]

hmm... maybe there is something wrong with your rotator cuff pulling the splinter bar handle :shifty:

lol jp i dont know anything dont mind me

 

[kingmidaz]

hmm... maybe there is something wrong with your rotator cuff pulling the splinter bar handle :shifty:

lol jp i dont know anything dont mind me

umm ok if you can't add anything helpful then you know what to do
:bsflag:

 

[CobraStar_LS8]

the noise gotta be coming from one place bro

 

[97stscaddy]

103,126 I change my oil every 4-5k....I use high performance 5-20 weight...not loud enough to be a valve rattle though

I was thinking more along the lines of rod knock or a wrist pin.

The timing chain sounds plausible though.

 

[BrklynExpress]

I have the same thing on WOT. my 90 taurus has the same sound. on the taurus its a loose heat shield. I assume its the same on the ls. Ill have them check it when I get my oil change

 

[sweetls]

I had the same exact thing on mine it took me forever to find it it turned out to be the torque converter sounded like it was coming from the engine good luck

 

[TDUB]

I had the same exact thing on mine it took me forever to find it it turned out to be the torque converter sounded like it was coming from the engine good luck

+1. I've posted about this before. I had the same problem when I bought my LS, it would rattle at lower speeds and then go away as I got faster. I had a feeling it was the torque converter after I got under the car and listened to it. The transmission shop originally told me it was the cats, so I took it took it to an exhaust shop and they told me that it was indeed coming from the tranny. So the trans shop swore up and down it was the flex plate, ended up swapping it but the noise was still there so I didn't pay for it. I took it in again and told them specifically to swap out the converter, and sure enough it fixed the noise.