General engine noise question

Reply Subscribe

Thread Tools

Search this Thread

Mar 21, 2010 | 03:21 PM

hfddauzat

Thread Starter

Teching In

iTrader: (1)

Joined: Mar 2010

Posts: 9

Likes: 0

General engine noise question

Would anyone mind explaining the symptoms and differences of each: Spun bearing, Piston slap, and valavetrain related problem

My 02 z28 ls1 bone stock w/50,000 miles has a tapping/ticking noise that is rpm subjective and goes away 100% once the motor is warm, does that generally point to piston slap or lazy lifter or maybe exhaust leak? I can hear it under the car just as good as opening the hood, can also hear it inside the car.

Also, If there are no oil pressure issues or oil consumption would that point to either piston slap or valvetrain related too?

I've searched other people's threads and some responses indicated spun bearing, and some responses were piston slap, which is why I started a new thread.

Mar 21, 2010 | 04:02 PM

19BLACKBIRD99

TECH Enthusiast

Joined: Jun 2009

Posts: 501

Likes: 0

From: Birmingham, Alabama

I think its just a normal sound, I've owned two F bodies, and they both do it until they were warm.

Mar 21, 2010 | 04:04 PM

Blackhawk777

TECH Resident

Joined: Feb 2006

Posts: 855

Likes: 0

From: Omahaish. Nebraska.

Piston slap from what I've heard is more of a slight knock when cold, but does go away as it warms up. Lifter noise and exhaust leaks are real similar in sound. If you can pinpoint exactly where it's coming from, it'll help big time in diagnosing it. I thought I had lifter tick at one point, but it's coming from a seam on my Y pipe, so no lifter worries, it's an exhaust leak. Piston slap has no real relation to oiling issues. valvetrain MIGHT affect oil pressure a little, but I would imagine it's not much. You would know a spun bearing instantly, so you can rule that out. lack of power, loud knocking and lots of oil issues IE no pressure, violently fluctuating pressure at idle..... all the fun stuff. Again, it all boils down to finding the exact area of the tick/tap.

Mar 21, 2010 | 04:07 PM

19BLACKBIRD99

TECH Enthusiast

Joined: Jun 2009

Posts: 501

Likes: 0

From: Birmingham, Alabama

Yeah, my old bird had and exhaust leak as well, and sounded the same

Mar 21, 2010 | 04:47 PM

95formulalt1

TECH Fanatic

iTrader: (13)

Joined: Oct 2005

Posts: 1,863

Likes: 1

From: NH

the TA does the same thing. a lil nose when cold then it warms up and its fine. my oil presure is about 60-70. in my old motor i spun a cam bearing and it sounded like hell. oil presure was down 25-40.
you could always use lucas oil adder to quit it down?!? maybe

Mar 21, 2010 | 04:59 PM

hfddauzat

Thread Starter

Teching In

iTrader: (1)

Joined: Mar 2010

Posts: 9

Likes: 0

Thanks for the fast replys, I just bought the car in dallas last week and drove it down to houston and it is super quick. It just bothers me, I don't even like to drive it when its ticking, It takes a good 8 min for it to warm up and quiet down before I even take off.

So as long as the noise goes away once it gets warm, there should not be anything to worry about? And when I mean warm I mean operating temp, not 30 seconds.

Mar 21, 2010 | 05:09 PM

95formulalt1

TECH Fanatic

iTrader: (13)

Joined: Oct 2005

Posts: 1,863

Likes: 1

From: NH

Quote:

Originally Posted by hfddauzat

if the noise didnt go away or got louder when it was at operating tem i would say you have a problem but its gone when its warm your ok. you should always let it warm up befor taking off. do an oil change and try the lucas oil adder. it will keep it quit.