lastcall190

iTrader: (36)

Sounds like it's coming from the top of the intake manifold, as about centered on the engine as you can get. But it's not always there. Its presence is not dictated by how hard I drive the car (which 5 days a week it's daily driven to and from work). It doesn't sound like a spun bearing (heard a vid of that, and this isn't a banging, but almost like an obnoxious monstrous exhaust leak), and I check my oil daily to make sure I'm not low. I know I have a few exhaust leaks regardless, but sometimes at idle it's almost louder than the exhaust/cam chop. I'd get a vid but it probably wouldn't show up, that's how erratic it is. oil pressure is just fine, level is fine, car pulls good (havent been taching up to 7k every day, but around town with a few WOT blasts every now and then it's without incident). Any ideas? I don't know if it's a loose rocker because wouldn't it be more constant than just "sometimes"? I know what piston slap sounded like before the cam, and it sounds nothing like this (well maybe just piston slap on steroids), and if that's what THIS is... holy hell. I have M1 5-30, which I've been told is on the thin side, I had my brother get me 12qts of Amsoil ASL 5-30 coming in tomorrow or Monday I'm switching to. Is it possible that it IS piston slap and the oil itself is just too thin for my application? I'm at a loss, but the car itself starts, idles, drives, fine. Weird...

-J

BlackSVT03

iTrader: (1)

If its the same noise that I had and countless others have had, then its probably a spun bearing or a seized lifter.


With some luck its just a broken push rod or a loose/broken rocker.

lastcall190

iTrader: (36)

Hmm... would the car still have good oil pressure and full power with either of them? I hope it's not I was hoping to at least get to winter before having to change anything drastic... Maybe I'll tear into the car next week and see if it's a PR or rocker. This is a distinct rhythmic tapping, not marbles in a can like I've heard some spun bearing cars With the hood closed you almost cant hear it. Granted I have a **** ton of exhaust leaks that might be messing with my ears (need to get 'em fixed I know).

-J

lastcall190

iTrader: (36)

Here's a vid. http://video.ls1tech.com/video/86659...7801392e06.htm Now that I watch it on video it sounds more like piston slap... maybe I just NEVER heard a car that had real piston slap versus light slap? Oh well lemme know waht you guys think, changed the oil today, ZERO metal on the plug, zero metal in the oil, full 5.5 qts give or take a few ounces drained.

lastcall190

iTrader: (36)

FWIW, the noise is nearly 100% gone. Last weekend I pulled the valve covers and rockers were all tight to spec. I was gonna pull the covers again and check PRs this weekend but I found the problem (99% sure at least, since the noise is almost completely gone). Almost ALL of my intake manifold bolts were loose, three were almost all the way backed out. I tightened all of them to spec and proper pattern (PITA with a cumbersome torque wrench but do-able). Little sewing machine noise now, no more near death idling issues, and almost no exhaust noise besides the typical "I am a long tube header so I'm a loud bastard" tick. Check your intake bolts if you have a tick that sounds like it's coming from top and center of the motor. Thanks.

-J