Knock when cold
#1
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Both my 2000 & 2001 Z28's knock quite a bit even at low speeds when cold. Is this piston slap, detonation, or anything serious that I should worry about?? It quiets down after a few minutes when they get warm. Both are fairly low mile cars. Could this be carbon buildup that is causing it?? Any remedies out there???
#2
10 Second Club
iTrader: (37)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Mine is doing the same thing. I seafoamed the upper part of the engine and when it didnt fix the issue I thought it was piston slap. I didnt worry about it and figured there was nothing short of a rebuild that was gonna fix it. I just got it back from an LS specialty shop and they told me its the lifters gummed up probably from a lack of maitenance from a previous owner. I just put some seafoam in the oil yesterday afternoon and drove about 35 miles non stop to the house. I went out at 4:00 this morning and started it to go to work and the noise has drastically reduced but not totally gone. The temp was about 30 degrees outside this morning and it would have normally sounded like a diamondback rattlesnake before the seafoam so Im gonna give it a couple of hundred miles to see what happens. Hope this works or its off with her heads!!!
BTW, does anyone know if the rocker bolts are TTY?
![Rolleyes](https://ls1tech.com/forums/images/smilies/LS1Tech/rolleyes.gif)
![Hijacked!](https://ls1tech.com/forums/images/smilies/myhijacked2.gif)
Last edited by JRENIGAR; 03-07-2014 at 10:53 AM.
#3
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
What do you remember about it? I stepped on a soccer ball once and flew backwards and landed on my head on the blacktop, knocking myself out cold. Next thing I knew, I was sitting at a friend's kitchen table with an icepack on my head
#4
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
![Sad](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_sad.gif)