There is a distinct rattle in my engine that is noticeable from the cabin especially between 2500 & 3500 RPM. It is loudest when the engine is cold. It has been there since I picked it up.
It sounds like piston slap to me but it's possibly the false knock I read about in another thread.
I run Entech 93.5 octane fuel. I tried adding some octane boost and that may have quieted it down some but I'm not sure.
My car is a 2001 Firehawk with just over 2k miles. It had 500 miles when I picked it up. It will rev happily to 6000 had hasn't come apart.
I was wondering if this was normal or what?

 

Mine does something almost exactly the same. It is a 2001 M6 Z-28. Just when it is cold. I don't think it is knock it would get louder. It kinda sounds valvetrainy to me. I just rolled 20,000 and have made 50 1/4 mile passes with it since Feb, I guess I am gonna live with it. Let me know what you find out. Throw me an E-mail. Now you got me worried, well a little anyway. <img src="gr_images/icons/wink.gif" border="0">

 

valvetrain on the newer ls1's seem to be loud...

 

Mine was loud.Ended up being a bad lifter.Dealer changed all of them.Now the noise is gone.

 

NO! I would take it back to the shop and have them look into it.

 

Sounds like knocking, take it to the dealer since you only have 2000 miles on it

 

Thanks for the input. It may be normal but it's pretty loud. It doesn't really sound like valvetrain to me. I guess I'll throw the factory intake stuff back on and try the dealer. I don't have a lot of faith in them though. <img src="gr_sad.gif" border="0"> I'll let you know how it goes Mike.

 

i think all 01 and 02 are alittle loud mine has a slight noise at start up but it goes away after ahwile and i don't baby my car either valvetrain parts aint gonna take that abuse for long if they are bad or defective

 

You know I listened to it real hard last night. (I put the cutout back on). I am sure it is piston slap. The higher end cars (Vettes for us F-body guys) got a tigher piston and special coating to clear it up. A guy I work with has a 2001 Trans am with 6,000 miles on it and his does it too. It has been considerablely cold here as of late so I am gonna let it warm up longer. If I had the dealer look at it by the time I got there the noise will have stopped and I don't want them screwing with my 318hp 330 ft/lb of torque engine.
<img src="graemlins/camaro.gif" border="0" alt="[Chevrolet]" />

 

[quote]Originally posted by LS1 Mopar Turbo:
[QB(]. I don't want them screwing with my 318hp 330 ft/lb of torque engine.
<img src="graemlins/camaro.gif" border="0" alt="[Chevrolet]" /> [/QB]<hr></blockquote>
are those stock dyno numbers

 

[quote]Originally posted by LS1 Mopar Turbo:
<strong>MTI Lid and 2 1/2 inch cutout.</strong><hr></blockquote>thats pretty good my 01 had 4000 miles when i did mine and with a K&N filter only it did 313rwhp and 336 rwtq it's a A4 too i haven't been back to the dyno sense and i have a few more things done to it a pulley will be my next mod

[ January 01, 2002: Message edited by: Red Dragon ]</p>

 

I am getting ready for Headers,FTRA and gears. As soon as I get the cash here in Jan. I am hopping for about 330 rwhp and 340 to 350 ft/lbs of torque.

 

[quote]Originally posted by LS1 Mopar Turbo:
<strong>I am getting ready for Headers,FTRA and gears. As soon as I get the cash here in Jan. I am hopping for about 330 rwhp and 340 to 350 ft/lbs of torque.</strong><hr></blockquote>im sure that FTRA will help ya out pretty good cause i have the BG ram air kit on my WS6 and i picked up 2mph with just that i could probaly get more if i didn't have my stock exhaust on there still but i like the stock look though keeps people guessin' about my car
<img src="gr_images/icons/cool.gif" border="0">

 

MTI Lid and 2 1/2 inch cutout.

 

Farhawk read this
http://www.c5registry.com/2k2z06/page5.htm
<img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" />

 

Mine does the same thing. It seems to get a little quieter when the engine warms up, but it is still noticable. I have 14000 miles on mine and it has done it since the day I got it, but it seems to be getting worse. I have the car put up for the winter, but maybe I should take it to the dealer now so if there is a problem and i can get it fixed before spring.
ps: Should I remove any of my mods before going to dealer?? I'm pretty sure none of them will void warranty. The only one I think might cause a problem is the 160 t-stat but I'm not sure.

 

Bottom line is I think these motor are noisy. Sometimes I think I a driving a damn diesel <img src="gr_images/icons/wink.gif" border="0"> The more I investigate the more I find people having this noise. If yours stays after warm up I would have them check it out. I would put it all back the way you got it though so you don't have to argue with them about warranty issues. <img src="graemlins/camaro.gif" border="0" alt="[Chevrolet]" />

 

It seems that the LS1's tend to be a little on the noisy side. Thanks for all the dialog and the Link that Mike sent http://www.c5registry.com/2k2z06/page5.htm <img src="graemlins/gr_hail.gif" border="0" alt="[hail]" />

I think I'm going to chill for a while and see what develops. I can live with the noise if it's 'normal' and it seems that it may be. My oil appears clear and the noise reduces dramatically once the engine gets hot. Plus, it seems to run strong. My feeling right now is that it is the piston slap mentioned in the link above. I have not had any big oil usage as yet though.
I will still take it to the Dealer when my schedule allows, or it gets worse, just to see what they have to say about it if nothing else.

 

Farhawk, my 2001 only has slight tick cold goes away when warm. I think a knock is a problem.
GM tightened up main bearing clearances on 2001(all)ls1's for noise issues, and all LS1"s after a certain build date got coated piston skirts to tighten up clearances in 2001. Stand firm with the dealer and they will have to resolve it.
Good luck.

 

Well I took the car in to the dealer yesterday. Today I got the answer I was expecting from them. They say it's normal noise from the valvetrain. I remain unconvinced. I plan to have them show me by firing up another one on the lot when I go there this afternoon. <img src="images/icons/rolleyes.gif" border="0">