z28_n_tx

iTrader: (7)

Ok heres the deal i have a 2001 camaro z28 auto, bought it 9 months ago used from a dealer (gm certified used vehicle)with46,500 miles on it....now at 51,200. well today after work one of my co workers happened to be around when i got in my car ... so he starts to look at it and tells me that he wants to look at the engine bay so i opened the hood and turn the car on, next thing i know he tells me that he hears a noise (engine knocking???)... i give it some gas and he still hears it , so i go close to the engine bay and heard it my self....so im freaked out now about it ...i came home let the car sit for about 30 min. went back outside to check it out again but i didnt hear it this time.. my engine is still a bit warm...but no knocking i took it out for a cruise windows down so i could listen for the knocking but none..any ideas?? a read some post about piston slap..not quite sure wether its bad or not..some say that it is suppose to it when engine is cold others say its not ...any help will be appreciated...

rayosequis

iTrader: (13)

LS1's are notorious for excessive valve train noise, and I believe that may have been what you heard.

Elite_Hot_Rod

I'm guessing probably alittle piston slap when it's cold, goes away when it warms up. Check your oil to be on the safe side. It's problematic with the LS1, nothing to worry about.

z28_n_tx

iTrader: (7)

i just went outside to check it out again and sure enough just for a minute or less but then went away the engine was a bit warm though so i believ it only does it when the engine is cold and once it warms up it goes away.. these posts confused me a bit ..https://ls1tech.com/forums/generation-iii-internal-engine/381954-what-piston-slap.html

so is the engine knocking the same as piston slap???

SSilverSSurfer

iTrader: (8)

yea its piston slap...it does og away when it warms up...NO knocking is not the same as piston slap! if it was knocking youd be in a little bit of trouble

Elite_Hot_Rod

I read that post also and Orangepeel doesn't know what he's talking about. Yes the knocking you hear is piston slap, it's not a big deal. They say it's caused by the short length of the piston skirts on an LS1 piston. Both of my LS1's did it.

z28_n_tx

iTrader: (7)

feel a bit better now thanks...(elite_hot_rod how did you make it go away??) oh and how is the engine knocking diff from piston slap?? does it sound the same??? my co worker said it was engine knocking....sorry for all the questions.. thanks again guys

SSilverSSurfer

iTrader: (8)

engine knocking means u messed the motor up pretty bad!!! LOL

Elite_Hot_Rod

You don't make it go away, you live with it, no biggie. There are 2 knock sensors mounted on top of the valley pan which pick up knock, if it's bad enough the PCM will pull timing and you should get an SES light if I remember correctly. This type of knock is fairly serious but I don't think that's what you are experiencing.

z28_n_tx

iTrader: (7)

so le tme get this straight ... piston slap never goes away but its not a prob?? so if i warm up the engine and still hear it but not as loud (to where you have get close to the engine is it the same prob?