j_dog25

I wanted to list a few problems I've been noticing with my LS1 and just see if any of you have noticed similar problems with your motors. Number 1 is the idle. From the day I picked up the car it has had a noticably rough idle. It's an M6 car and I can see and feel it in the gear shift when sitting still. Number 2 is the sulphur smell that seems to be becoming more prominent. I always run 93 or 94 octane fuel if that helps. Number 3 is the audible pop or backfire I seem to get between shifts for the first few minutes after startup. This seems to go away after a while. Number 4 is the knocking or slapping I often hear in the motor after startup. It isn't extremely loud and pronounced like a loose rod but it still concerns me. sometimes it's there and sometimes it isn't. And it doesn't seem to matter whether the motor is hot or cold.
Anyone out there have any info for me?
Greatly appreciated
2002 Z28 LS1 Barebones almost no options except T-Tops
13,000 Miles, Oil Mobile 1, car is completely stock no mods
M-6 Trans

CPFarhood

1 & 2 sound like catylitic convertor problems to me, 3 is due to not matching revs when you shift, 4 is piston slap, lots of ls1s have it, don't count on getting it fixed under warranty.

rncotton

Rough idle -- normal. You should see the shift handle shaking while you're at idle. My car *almost* sounds like I've switched to a different cam.

Sulfer smell -- ??? I dunno Cats going out can create a sulfer smell or a rotten egg smell

Pops/backfires -- normal. Our cars run rich, especially at startup. Add an open cutout and wake up your neighbors.

Slapping -- Normal. This is the infamous piston slap. It goes away after the car warms up. Our alum. block expands when it heats up, so when it's still cold, there is a bit of play in the parts.

stik6shift98

catalyc converters might be bad.....

whats your oil pressure at?
when warm at idle and when cold at idle

fbird95

The rough idle is definatly normal, the sulfur smell, one more vote for the cat(s), as for the noise i would have to hear, could just be piston slap common to LS1s, espcially when the choke is on after start up.

Ryuhei

The shift **** vibrating is normal. If you ever get an aftermarket shifter, expect MORE vibration and noise. The backfiring shortly after startup is normal as well. I like when mine does that!

I've been lucky with the piston slap issue, I haven't had it. I dunno what the sulphur smell might be.

j_dog25

Thx for the info people. It's good to know that much of this is common. I have to take the car back to the dealer for a few other things that are goin' on with it that are definitely not normal so I'll ask em about the exhaust smell when I do that. Oh, how much luck have ppl been having with getting the dealers to fix their differential problems? I've got the clunking and thuds thing going on which seems to be a problem on alot of Zexel Torsen cars. I noticed the other day that the pinion seal is leaking already so they are going to at least fix that.
Thanx again!

rncotton

Good luck with your pinion seal. The dealer replaced my leaking pinion seal under warranty and 4 days later the whole rear grenaded while I was driving at 65 MPH on the interstate.

Rebuilding the rear was denied as a warranty claim, so I had to pay that out of my pocket.

CPFarhood

I think i'd be calling the BBB about that one. That or report them to the DOT for faulty work on the pinion seal replacement, or both.

Coop

rncotton!!! How long ago did this happen?? Mine did the EXACTLY same thing. Although I have some friends that work for that dealership and I found out what REALLY happened:

When my car went in to get the pinion seal replaced the *****ing moron that did it was not even a certified tech, he was "GETTING READY" to go into school for it!!!! Well what the idiot did was overtorqe the bolts that went back in and that lead to the distruction of my rear end! Mine got fixed under warranty though. You should go up there and ask why a rear end would fail going down the highway at 65mph??? I was waiting for them to say something to me about me ******* the car or something and that's why it blew, and I was going to tell them that if going 70mph in 6th gear is ******* this car you can *****ing have it!!!


GO BACK AND FIGHT THIS!!

96Z28/93TA

yip, if you overtighten or under tighten the pinion nut you will have bearing failure or broken gears. your dealership SHOULD have fixed it under warranty.. my dealership would have.

Ryuhei

Good luck on getting the rear end noise fixed. It probably won't happen. I've brought mine in twice for it (I have under 10,000 miles, never been to the track) and they make a few adjustments and say that's all they can do. I think these rear ends are just crap and we have to live with the noise. Mine's working fine, it's just noisy. I'm not going to go back unless it blows up.

Bob Schaefer

At about 32,000 my pinion seal started weeping. The dealer 'fixed' it under warranty. 9000 miles later the new pinion seal was leaking big time. Dealer 'fixed' again under warranty although car had more than 36000 miles. The rear end got progressive noiseier until at 46000 miles the replaced the pinion bearings, etc. This was all their fault for not having properly set the pinion preload in the first place. All was done at no cost to me.

Bob Schaefer

I too have always had this same thing, and think it is normal. It has absolutely nothing to do with matching revs.....it happens as the throttle is closed before re-engaging the clutch.

rncotton

For those that asked:

My pinion / rear issues were about 3 weeks ago. In hindsight, we know that the pinion bearing started acting up about two months ago as one bearing seized and started to wear down the pinion. Eventually, the pinion seal failed, which the warranty company (Wynne's) paid to have it replaced. 4 days later, the pinion bearing completely cut loose, trashing the rear.

There was nothing the tech could have done about it, nor could he have known about the pinion bearing problem without cracking it open, which you don't do for a pinion seal replacement.

The warranty company states they won't pay on the claim since it was caused by "lack of lubrication", even though it was the pinion failure which caused the lack of lubrication.

Think of it this way .... you're driving along and your oil plug falls out, dumping your motor oil on the highway. Your engine seizes since it doesn't have oil. The motor is not covered under Wynne's warranty since the damage was caused by "Lack of Lubrication", even though the failure can be directly tied to the oil plug falling out.

So ... I paid for the repair, cancelled the warranty, and started litigation. Because of the pending legal claims, I can't say any more about this situation.