KevsLS1

Well I finally got around to taking a video of the noise I hear everytime I start my car .

Now when I uploaded it on to this site, you can't really hear the noise anymore. But on Quicktime you can hear it perfectly.

here's the link to the video

http://video.ls1tech.com/video/0CFB4...3AC75D4006.htm

about 2 mins into the vid if you listen closely that's what I hear, it's really loud, and lasts like a good 10 mins or so and then finnally goes away leaving just a little sound what you would have to REALLLY listen for.

What would it be?

Also when I give it some gas and let go you can here it speed up then drop back to it's normal sound , and other times you give it gas it does the noise again but when dropping back down to normal idle it's not even there anymore., but then shortly after comes back.

anthonyz281999

iTrader: (4)

well if it goes away ...id say its piston slap... but i could be wrong

anthonyz281999

iTrader: (4)

nice paint too btw

777

iTrader: (21)

You could hear it a lot better if the hood was open I'd say that's lifter tick. Mine had it/has it again now.

Fenster

iTrader: (3)

Piston slap SHOULD go away after the first 45 seconds to 2 minutes of run time according to several GM engineers I talked to up in Detroit when I was there for NAIAS. I'd say you are probably looking at a little lifter tick. If it goes away its probably a lifter on its way out, but is holding on for dear life for you.

Firebirdfan

What is piston slap? What is lifter tick? Sorry, I'm new....

777

iTrader: (21)

Piston slap is a tapping noise on cold starts on the lsX based engine due to loose tolerances. When they heat up the tolerances are right and it no longer ticks.

Lifter tick is when your lifters are about to crap out and they tap no matter what. However it could be a variety of things like incorrect pre-load, loose lifters, broken springs, etc...

Fenster

iTrader: (3)

Piston slap has less to do w/ tolerances than people thing accordin to the engineers I talked to. What GM did w/ the LS based motors to help w/ eeking out every available hp they could, is to actually shrink the skirt on the piston. Its hard to explain in writing, but by shrinkin the skirt and making the piston shorter, you effectively reduce the amount of friction area. But by reducing total piston height, you allow more "wobble" possibilities. Piston slap is that wobble. The piston wobbles in the cylinder until it warms up to appropriate tempreature. There isn't actually any difference in tolerances between the LS motors and previous motors. Combined w/ the shrunken piston skirt, you also have in use an alloy that has more expansion characteristics. There is nothing wrong w/ the piston slap unless you abuse the car while its doing it. Engineers said they have tested motors for 500k miles w/ no detrimental wear from the piston slap issues on these motors.

777

iTrader: (21)

I would consider anything that could "wobble" to be a loose tolerance just like I said. When it heats up the tolerance get's smaller. Unless I'm just using tolerance in a different context than what you thought I was meaning it as.

Fenster

iTrader: (3)

I wish I could physically show what I mean. I may have to go into paint and draw what I'm referring to. every piston "wobbles" in the cylinder to a certain extent. Rock if you want to call it that. The LS based pistons are shorter, thus even w/ the same tolerances (piston to call clearance) as a taller piston, which they have to have due to expansion characteristics, you will have more rock until expansion is complete due to less surface area able to contact. Think of putting one smaller glass into a bigger one. Rock the smaller glass inside the larger one. Now take an identically wide glass as the smaller one, but short, and do the same thing inside the larger glass. You will notice the shorter one rocks more, even though the tolerances are exactly the same.

We are probably just thinking about two similar, but different definitions.

I just get sick of people bitching about a "problem" thats really not a problem to begin with. GM has studied the situation, and stated its nothing to worry with.

KevsLS1

Ohh yay looks like engine work for me at 677 miles

777

iTrader: (21)

We are thinking of the same thing. I understand you.

SailorZ28

So if my Z28 doesn't have any ticking at all...even on cold starts, that's a really good thing right?

Z-Convert

**** it! Drive it till it blows then worry about it.

Flash99

iTrader: (48)

777

iTrader: (21)

It doesn't really matter. Piston slap isn't bad. It's not a problem. It's just part of the engine.

ws6pewter

iTrader: (1)

mMne makes the exact same sound. After it warms up you can barely here it unless you get under car or bring the rpm's up. From what i have read the piston slap should go away once the engine up to temp. I have the extended warranty so i plan on taking to the dealer sometime soon and have listen to it since it seems to be getting worse. btw I only have 25,000 miles on the car.
I'll post what i find out.

KevsLS1

That would be greatly appreciated THANKS!.

I went to the dealership and they put in an additive called "lubricity" well I've put on about 100 miles and it still ticks , I still have warranty but they say drive it around more . I'm quite ticked the car has only 841 miles now.

MJK

iTrader: (3)

Hmmmm..Some sort of additive?I dunno about that.Maybe try a different dealer if there is another around your area.

My car always sounds "ticky/tappy" when cold and goes away once warmed..This is my 3rd LS1 and they have all done it..One of which was bought new in 98'.

800+???Is that the actual milage on your TA??If so...AWESOME!Should post some more vids or pics at least...

Good luck!

mc01ta

maybe this is your cars' way of saying drive me with only 800 miles...sounds like piston slap to me. Good oil pressure? Good power? Get it scanned and check the pushrods. Start with small troubleshooting for a tick. Check all plug wires to make sure they are on tight. Make sure no air check valves are bad. Make sure no exhaust leaks. All of these can make a tick or tap. Use the damn search button on this board for tick and it will provide you some ideas on where to start looking.