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Ok I have a few questions about engine noises. First off. my car has 20,000mi.

#1 I start up my car at idle and when it heats up.. I hear a slight knock on the drivers side, people have told me this is most likely an LS1 piston slap, because after i get on my car hard.. it goes away, and its really only there from 2k to 2.5k anyways, after i get into high rpms it goes away.

#2 I was revving my car very slowly today after i put oil in it, to make sure my pressure was ok (only revving to about 2-2.5k rpms after it was at opertating temp). It revved up fine, but when it was coming down from the rev.. It almost sounded like something was .. rattling.. inside the egnine?? I decided to take it for a drive after i heard this.. it run fine! I streched 1st and 2nd gear both to 5.8k rpms without any problems, full power all the way through.

#3 Tonight, my "low oil" light came on.. I just changed my oil about a month ago and it was 1.5 quarts low.. WTF (Mobile 1 5w 30)? No oil on the ground, and no leaks that we could see under the car at all.. My step-dad was telling me about how these motors were built loose for better performance, and it would use up a bit of oil. Who knows if this is true.. o_O


None of the noises here affect my performance, I ran a 13.3 at the track just like 3 weeks ago, with these same noises, and my minimal mods.

Do I have anything to worry about? Anyone else have these similar noises and oil loss?

I have an extended GM warrenty from 3yrs/36k miles.. it's a $100 deductable.. but before I get to 36k miles.. I'm going to take it in and have them fix every i can find wrong.

Gauge

iTrader: (3)

#1) This sounds like piston slap to me. If you could post a video, I'm sure someone coule help you identify it.

#2) Can you determine where this rattle is coming from? It might just be normal valvetrain noise. These cars can make some interesting sounds in the top end.

#3) How many miles did you drive in that month? LS1s are notorious for drinking up the oil. Most people claim to lose around a quart every 3k miles or so. I've heard much worse. Any white smoke on startup or at WOT?

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#1 I'll try to get a video tomorrow

#2 Thats probably what it is.. Nothing really shakes, and the rattle isn't intense at all, its more of a noise then anything actually rattling, thats just the best word to describe it. The egine doesn't shake or anything.

#3 I'll say ive driven about 2k-2.2k miles. No white smoke at startup, not any smoke for that matter.

Thanks for your help, anyone else have suggestions?

Gauge

iTrader: (3)

The rattling sound could also be "deisling." Have you had the car tuned? Any other work not in your sig?

As for the oil loss, you may want to check your PCV system. If you have a bunch of oil in the PCV lines, then you might consider getting a catch can to alleviate the problem.

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What exactly is.. deisling.. that doesn't sound so good.

No my car has the factory tune, I don't really have any mods that would require a new tune yet.. After I install my headers and 3.73 i will be getting a tune though.

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dictionary.com ~

dieseling- the continued running of an internal-combustion engine after the ignition is switched off

I don't think thats wat it is, because the ignition was still turned on , and my car was still running when it came down from the rev is when it made this rattling noise.

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iTrader: (3)

That's not what I was referring to. Deisling is a term that some people use for a sound that your engine can make... I've only heard it in person a couple of times, and once was in a friend's Mustang GT. He got a tune that had too much timing advance in the low RPMs (under 2200). If he pegged the gas in that RPM range the car just made a strange rattling sound. He pulled the timing back and the issue was gone. I would assume it's just a form of knock, but I'm not really sure what causes it. It certainly didn't sound like a normal detonation issue to me.

You probably don't have this issue. I'm just sorta thinking out loud... with a keyboard.

BLKWS.6

#1 Piston slap, dont beat on it when its cold

#2 I bet it sounds like a bunch of BB's on deceleration from 2-1000 rpm. This is your roller/rocker arms. Normal, my 5.0 that I put RR's in did it WAY louder.

#3 My car likes M1 10-30EP and uses no oil, yours may like a 40 weight. Try 0-30 German Castrol. A lot of ppl have luck with it if their car doesnt like the lighter stuff.

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Thanks for the #2 help! I'll try a different oil next time I do a change.. need to find out where I can get that German stuff around here in Memphis, TN.

I had my friend thats a mechanic listen to it, he described exactly what you said.. the roller/rocker arms and I had nothing to worry about. Unfortunitly, I am still a bit novice with engine mechanics.. but i'm trying to learn more so I won't have to ask these things when I hear / feel stuff in my engine.

Fedge

iTrader: (3)

i complained about the same thing...was gentle on the car and a month later at least one rod bearing went south


good luck, hope it's nothing

Cop Car

iTrader: (14)

dude you are fine

my 160,000 mile LS1 sounds like a diesel. keep running the crap out of your car, if something is going to go wrong its going to go wrong. just make sure it goes out before 36,000 miles

Fedge

iTrader: (3)

that is just so unfair. 'dude you are fine' was what a few people told me...and now my sig is 3 lines longer

Cop Car

iTrader: (14)

yeah, well if there IS a problem he needs to make it a more tangable problem before the warranty will do anything about it and the warranty is about to expire..

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well my car doesn't often see over 2.5k rpms.. i never really beat the crap out of it, mainly because i can't afford the gas

Every once in a while, when im coming home from work on the interstate, and i see a ricer... well you know. But thats about the only time i open her up.

BLKWS.6

roller rockers make noise and ls1's slap.its fine.

BLKWS.6

http://s29.photobucket.com/albums/c2...nsam005avi.flv

^this is rocker arms (louder than mine though) But I bet thats what you hear. Its normal.

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sounds exactly like my engine.. thanks alot!

GGTTOO

iTrader: (2)

Ok guys I know this is an old thread, but talk to me about white smoke at startup. I have an '04 GTO, which has been modded quite a bit. Recently, I had a H/C package installed and am noticing a puff of white smoke at startup. What do I need to look for and how concerned should I be?

Any input would be appreciated.

Thanks in advance.

Gauge

iTrader: (3)

Can you provide some more details about what's been put on the car and what kind of oil consumption you're seeing (x number of quarts lost in y number of miles)? Do you have to let the car sit for a while before it will smoke, or will it happen when you start it up right after killing it?

Any chance of a vid?

GGTTOO

iTrader: (2)

My mods are as follows: '04 PBM GTO, SLP ML headers, Custom 3" Exhaust, Lingenfelter CAI, NGK TR55, Hellraiser TQ cam, Dart heads with Gen4 springs, BBK IM with 85mm TB, gauge cluster mod, Aeroforce gauges in gauge pod, custom tune.

I just noticed the smoke yesterday when I started the car to go home from work. It appears that it needs to sit for a while. This morning when I started it it did not smoke at all. The temp this morning was around 65 and yesterday when I went home it was around 95.

It produced a pretty good puff and then went away and I did not see the rest of the way home. We were haveing trouble getting this car to idle with the new 85mm TB from BBK so the guy came and retuned it to idle better. It was hanging up aroung 1,500 until I came to a compete stop then would take a few seconds to settle down to the 825 PRM set point.

As far as oil usage, I have not seen any problem there as the car only has about 300 miles on it since the H/C change. It did die after the smoke came from the car yeaterday and it took a few revs to start back up. Once it was started though it did fine.

If you need any other info let me know.