98RedBird

iTrader: (77)

I posted a little while ago about my car having a knocking sound then vanishing when the car gets warm. The more I read I'm getting convinced it's piston slap rather than a rod knock because it only happens on cold starts and then goes away within ten minutes when the car is warmed up. I took two video's to see what you guy's thought.

Here's the first, cold... start...http://s190.photobucket.com/albums/z...t=MVI_0839.flv

And here's the second, about 10 minutes after cold start, the car is warm now...http://s190.photobucket.com/albums/z...t=MVI_0840.flv

As you can see, in the second video the sound is completely gone. I am doing Heads/Cam here very soon (I have the cam and am just waiting for the heads) and while I was in there I was doing rod bolts and wanted to check the rod bearings just to make sure. I drained the oil and there was nothing to speak of in the oil. Just a small amount of greyish sludge on the oil drain plug. Other than that the oil looked clean. When I drain it the next time I will cut the filter as well to see what I can find.

So what do you guys think? Am I being overly paranoid or does this sound like a problem. I just don't want to go further with the heads/cam without knowing for sure about the bottom end.

Thanks for the help!

hirdlej

iTrader: (31)

You're being overly paranoid. That's just piston slap, If it was a knock it'd get louder after it warms up, Don't worry about it

98RedBird

iTrader: (77)

Okay, thanks. I just wanted to make sure before I plow forward to heads/cam/intake/tranny ect...

trc725

change the oil to a syn and a lot of that will go away if you are in a warm climate 10/30 or better ho you can go as high to a 5w40 syn not conventional comes in varrious taste mobil/valvoline/even rotella has a syn oil castrol and the list goes on even walmart has a syn oil i use it 13.85 for 5 quarts in a jug you will see a gas saving of 3to 5% the real drawback is you may see seapage at the rear and front seal thats why they make carwashes you will also see less fouling

99mongooSS

iTrader: (4)

just piston slap. when I had a knock in my engine,it got progressively louder untill it finally sounded like a monkey with a coffee can and a stick got loose inside.

98RedBird

iTrader: (77)

Well right now I'm using, and have been using Mobil 1 0W-40 because I read on here a while back that it had one of the best additive packages. Should I switch to a different weight ya think?

Thanks

TLUZLS1

iTrader: (6)

+1. You're ok...

Oh, and i think your oil is fine. I ran that through mine and was pleased with it, im currently running amsoil 5w-30 and can't tell a diff. between the 2.

2000NavyZ

iTrader: (8)

thats the same exact way my car sounds....haha i was worried for a while too. until i heard one that was much worse

98RedBird

iTrader: (77)

I know this has probably been beaten to death but it's amazing to me that GM didn't do anything to right this issue. I can only imagine the amount of people that didn't understand and raised hell at local dealerships only to have GM say we're not gonna fix it, it's normal.

I understand it's not going to hurt the motor at all but I'm sure there are alot of people out there that don't get that and just say hey, my motor is making all kinds of noises, WTF?

stefan256

iTrader: (1)

wow this post saved me alot of time i was trying to figure out what noise was coming from under the hood sounds exactly like this so im thinking im good

qwk93ta

iTrader: (13)

I've got the same sound, but it does not happen everytime I start the car; maybe every third or fourth time!!!