bushman

New to the forum and mainly due this this experiance. Two weeks ago i traded my 03 350z in for 2010 cobalt ss with a gm stage 1 kit already installed with 18,000 miles on it. Car flys and is alot of fun, after about 500 miles and 7 days of owning it i was driving home late at night when i shifted 2nd to 3rd at redline getting onto the highway. Right as i hit 3rd i got a big hesitation and the engine light came on. I pulled over looked at all the piping hoping for a pipe separation but found nothing wrong. Started the car back up and had a very gurgally exhaust note but no knocking or pinging sounds and idled fine. So i was able to drive it 10 min home oil temp and pressure fine coolant fine but just would hesitate with any acceleration. Next day called the dealership and was told to bring it into the dealership closest to my house, which was not the one i bought it from since it was under bumper to bumper. After dealer #1 having it for 4 days they concluded they were not going to work on it because the stage 1 kit did not show up on the car report as being installed at a dealer. Pissed off i called the dealer that i bought it from and they flatbeded it back to their dealership and gave me a rental for free and have been taking good care of the situation. After a couple days they let me know that it looked like a bomb went off in the head, damaged cam shaft and valves with springs. They said they found the dealership info where the kit was put on and that they were repairing my car under the bumper to bumper warranty that they told me the car was under when i bought the car 9 days prior, but they were gonna return the car back to stock. They were taking pics of the motor and sending them to gm as well and said the failure was in result of the stage kit not having a rev limit and revving to high, but if i recall it is just changed to 6500 right? So i talked to my sales person to be reimbursed for the extra amount i paid for the car having the kit already installed or be compensated somehow or to keep the kit on the car under warranty. I am supposed to hear the decision and get my car back later this week. Whats your guys impression on this situation?

N1ckateen

iTrader: (1)

i'd say either tell them to leave the kit on because that stage kit is supposed to be safe and warrantied or get a full refund of the stage kit. or tell them to take the car and shove it!

sponge14

Yeah there's no way I would take the car back with less parts then when I brought it in.

While they are at it, why don't the put the LT motor in it for you?

08SSTCRD

Haven't ever heard of that happening, very strange.

I'd like to know what actually failed, causing the head to become damaged.

Very unlikely it has anything to do with the Stage 1 kit. Sounds more like a factory defect.

MastaShaKe_88

iTrader: (5)

That does sound weird, and I'd like to know what happened as well.. If anything, GMstage 1 was a dealer installed option and its covered under warranty.. They can return it to stock, but I'd have em put GMS1 back on there CORRECTLY so that theres no problems this time.. If theres really a problem, and/or they wont cover it, call GM, cuz thats rediculous

emiller

Did someone tune the car after the GMS1 was installed and remove or increased the rev limiter?

What RPM were you shifting at?

bushman

Honestly was watching for deer on this back roads highway and had my eyes mostly on the road, but was about at 60 when i shifted. And i bought the car from a chev dealership and they just knew it had a stage kit on it no other info given. Definetly did not bounce it off any type of limiter though, i think its an exuse to not have any other warranty issues and not wanting to fix it anymore.

turbo86

iTrader: (4)

This is extremely odd imo. I wonder if the car was serviced properly, previous to Head explosion. Let us know what they find. This makes no sense at all.

emiller

Stock 2nd gear tops out in the mid 60s.

N1ckateen

iTrader: (1)

if u really wanted u could always slowly rev it until u find a limiter just to see where it's set at since the damage is already done especially.

JustACobalt

iTrader: (1)

very very odd that the valvetrain let go at 6500 anyways. there must have been atleast one broken lash adjuster prior to this happening. mine let go a few months ago and blew 7 rockers off the exhaust side but i was revving to 7k. keep us updated!

seeyaass

Sorry to hear that, but at least the dealership is taking care of you!

CudaJoe

iTrader: (1)

wow! a turbo cobalt still under the bumper to bumper!!! thats pretty impressive . Tell them to keep the stage kit on there, you'll probably be dissappointed with the inadequate power from what you were used to. Theres no way moving the redline from 6200rpms to 6500rpms is what caused the issue. They designed the kit, they put R&D into it, they knew that would never happen. Something else was wrong on the car before that occurred.

Gremlin85

iTrader: (8)

I'm glad you're being taken care of and that it'll be warrantied for you. It's always a shame to hear of a new owner having problems like this right out of the gate and with such low mileage. I can see how some might even get the impression that these are not reliable. But that's not really the case... I keep seeing more and more threads and posts of valve train going haywire.

But a couple things did come to mind...

18,000 miles, GMS1 already installed, second hand... previous owner just might have beaten on it pretty good early on in it's life.

Now, I don't want to sound like a dick or condesending what-so-ever... but are you absolutely 100% sure that you didn't miss the shift into third and maybe hit 1st or just no gear at all?

RYRO14

iTrader: (1)

Sounds like the car was over-reved to me.

umrdyldo

iTrader: (1)

I agree.

I have done this in a cobalt.

If you downshift and the revs are above the limiter then there is no limiter.

You probably down shifted to early and fucked up the top end.

bushman

Was definetly a 2nd to 3rd shift cause i kept it into 3rd as i slowed to the side of the road. Am wondering if in between shifts if it reved in neutral to redline and then hitting full boost in 3rd so high up if it caused it but you would think thats what a limiter is for. The dealership thinks that the limiter might have been taken off at the dealer who installed the kit.

bushman

Just got off with the service mgr, they said that they had the car all wrapped up today with new head internals but found as they put the head on the block that the head is warped too. So they say after they order a new head i should get the car back in about a week,AND THEY WERE TOLD BY GM TO LEAVE THE STAGE KIT ON AND RETURN IT TO ME THE WAY I BOUGHT IT.

bushman

The service mgr. has been pretty cool except for a few comments like "well how many times did you go past redline" or "you must have been driving this thing really hard" but my favorite blaming comment was " dont know what you did to warp the head". All i can say is my average mpg in 7 days is 27mpg ive put 500 miles on the car, and i know how to drive well enough to never have blown up the 03 350z i traded into you guys and never blew up my 03 evo. Regrdless of how i drive it this should not be able to happen on an all gm factory parts car period. But im getting it back and with the kit on it still so i cant be too upset except i have had my fill of this rental impala.

emiller

You bought it used from a dealer so you don't know what the previous owner did to it though. They could have had it apart or over heated it and warped the head. They could have over revved it too causing the initial damage and you simply revving near the redline finished it off.

Glad to hear its covered though since you didn't tune it and likely didn't over rev it.

bushman

Thanks for all the imput guys.

PrincessTurbo

for god sakes don't do that... WTF man seriously

PrincessTurbo

Thats not true , a fail safe does exist . Maybe yours is broke ..

It should throw it out of gear into neutral going above your desired rev limiter ..

If I cared to blow a car up I would go do a video and prove it to you.

Most shouldn't allow you to put it into a certain gear if you are at a certain speed some resistance lies in the shifter trying to go into the next gear until you get it to a lower speed,

Try it some time , Pull it out of third let it coast gently with the clutch all the way in rest the shifter pushing in towards the number 2 gear selection .. Wait till it slows down and it goes into gear .

It's how it works

At least mine does.

ronn

iTrader: (3)

HMM..
How's the ECU gonna *block* you on a down shift? What's the electronic mechanism to accomplish that? I don't think the ECU has any control over the mechanical aspects of shifting at all. ECU can only manipulate the motor..so it can cut fuel at the rev limit.

gotboost?17

iTrader: (46)

princess u r so wrong lol