It just doesn't add up.. :crazy:
[Z06] Z Running really bad
Instructor
Joined: Sep 2001
Posts: 149
Likes: 0
Re: Z Running really bad (BLACK/BLACKZ06)
I don't suppose anyone could have driven it while you slept? Just a thought.
I don't follow the line that 'bent valves = customer over rev'. HOW do they know a valve didn't get stuck in the guide and held open?? I valve spring failure could also cause float.
The stuck valve is also consistent with your original story 'put it to bed, everything was fine. cold start = bad.'
[Modified by BrianK, 11:44 PM 11/13/2001]
I don't follow the line that 'bent valves = customer over rev'. HOW do they know a valve didn't get stuck in the guide and held open?? I valve spring failure could also cause float.
The stuck valve is also consistent with your original story 'put it to bed, everything was fine. cold start = bad.'
[Modified by BrianK, 11:44 PM 11/13/2001]
Thread Starter
Instructor
Joined: Dec 2000
Posts: 218
Likes: 0
From: Columbus Indiana
Re: Z Running really bad (BrianK)
No one else around to drive it...not a posibility.
I'm not really sure how they determined that a valve was even bent?
The only comment I received from the dealer was....
"With the compression loss on cylinder #4 and all 8 cylinders misfiring
as recorded by the tech2...GM conclusion overrev was caused by down
shifting exceecing 7300 RPM."
To me, it doesn't seem very conclusive...but the dealer said that
GM is positive... :bs
I'm not really sure how they determined that a valve was even bent?
The only comment I received from the dealer was....
"With the compression loss on cylinder #4 and all 8 cylinders misfiring
as recorded by the tech2...GM conclusion overrev was caused by down
shifting exceecing 7300 RPM."
To me, it doesn't seem very conclusive...but the dealer said that
GM is positive... :bs
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Re: Z Running really bad (BLACK/BLACKZ06)
Have you considered the "over rev" condition "may" have happened at the first dealership that worked on the car?
I know it won't help your situation but I'd just about bet 5 bucks to a donut they revved the s**t out of it while they were trying to diagnose the original problem.
If you KNOW you didn't do it . . .then that just about leaves THEM to have performed the dastardly deed.
Maybe during a "test drive" for diagnosis purposes.
Too bad the "flight data recorder" doesn't record incidents like this so a
DEFINITIVE diagnosis could be made as to what happened and when it happened.
Then you could PROVE it happened while the dealer had the car.
GM should fix the darn thing anyway to maintain customer "goodwill".
Sorry about your misfortune and good luck on the engine repairs.
[Modified by VetNutJim, 2:34 PM 11/14/2001]
I know it won't help your situation but I'd just about bet 5 bucks to a donut they revved the s**t out of it while they were trying to diagnose the original problem.
If you KNOW you didn't do it . . .then that just about leaves THEM to have performed the dastardly deed.
Maybe during a "test drive" for diagnosis purposes.
Too bad the "flight data recorder" doesn't record incidents like this so a
DEFINITIVE diagnosis could be made as to what happened and when it happened.
Then you could PROVE it happened while the dealer had the car.
GM should fix the darn thing anyway to maintain customer "goodwill".
Sorry about your misfortune and good luck on the engine repairs.
[Modified by VetNutJim, 2:34 PM 11/14/2001]
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Re: Z Running really bad (VetNutJim)
Well, I ain't through yet.
If dealer # 1 , who had the car to diagnose it, reported all the symptoms to GM who reccomended a MAF change . . . .
How the heck did the diagnosis get from MAF to floated valves?
Don't seem possible.
I feel dealer # 1 accurately reported the symptoms to GM tech so . . .
The valves weren't bent then . . . .or the symptoms they were reporting to get a technical diagnosis would have indicated so . . .right?
There's something smelly going on here guys . . . .
Sounds like a good chance dealer #1 FUBAR'ed the man's engine.
But that's just my opinion and I know everyone has one of those.
If dealer # 1 , who had the car to diagnose it, reported all the symptoms to GM who reccomended a MAF change . . . .
How the heck did the diagnosis get from MAF to floated valves?
Don't seem possible.
I feel dealer # 1 accurately reported the symptoms to GM tech so . . .
The valves weren't bent then . . . .or the symptoms they were reporting to get a technical diagnosis would have indicated so . . .right?
There's something smelly going on here guys . . . .
Sounds like a good chance dealer #1 FUBAR'ed the man's engine.
But that's just my opinion and I know everyone has one of those.
Thread Starter
Instructor
Joined: Dec 2000
Posts: 218
Likes: 0
From: Columbus Indiana
Re: Z Running really bad (White_98)
The 1st dealer that I took it to said they couldn't find anything wrong...
Fuel pressure ok, compression on all cylinders ok, they even removed the rocker arms and said all valves were opening and closing ok, fuel injectors pulled and checked ok. No codes other than misfire on all 8 cylinders.
All readings on tech2 normal.
Notice in my sig that I have a cam installed...so when the 1st dealer told me that everything mechanical checked ok, compression / valves etc. I stayed with the Idea that it would still be a warranty issue. Probably just an electrical problem that they didn't have the expertise to resolve.
So off to dealer #2...Now I have a compression loss in #4 cylinder?
Had dealer #1 told me that there was no compression in #4, I would have stopped right there...have them put it back together...and accept the responsibility to make the repairs myself and that would be the end of the story...no problem...
I will never / ever leave my car at any dealer unattended...I’m not certain what either dealer did and worse yet no way to prove it. This is my 4th vette, 2nd C5 and never have I encountered this type of treatment.
The Black Z will have a new set of stage II heads from Katech..On order.
The whole thing still makes me kinda sick though... :U
Fuel pressure ok, compression on all cylinders ok, they even removed the rocker arms and said all valves were opening and closing ok, fuel injectors pulled and checked ok. No codes other than misfire on all 8 cylinders.
All readings on tech2 normal.
Notice in my sig that I have a cam installed...so when the 1st dealer told me that everything mechanical checked ok, compression / valves etc. I stayed with the Idea that it would still be a warranty issue. Probably just an electrical problem that they didn't have the expertise to resolve.
So off to dealer #2...Now I have a compression loss in #4 cylinder?
Had dealer #1 told me that there was no compression in #4, I would have stopped right there...have them put it back together...and accept the responsibility to make the repairs myself and that would be the end of the story...no problem...
I will never / ever leave my car at any dealer unattended...I’m not certain what either dealer did and worse yet no way to prove it. This is my 4th vette, 2nd C5 and never have I encountered this type of treatment.
The Black Z will have a new set of stage II heads from Katech..On order.
The whole thing still makes me kinda sick though... :U
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Le Mans Master
Joined: Sep 2000
Posts: 6,518
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From: Toms River NJ
Cruise-In II Veteran
Cruise-In III Veteran
Re: Z Running really bad (BLACK/BLACKZ06)
Hey Black,
You seem to be a huge Katech fan. Can you give us part #'s and/or prices, in email - if not here - on the cam, your pcm and the heads you have on order. I am curious, and was looking at the same mods.
You seem to be a huge Katech fan. Can you give us part #'s and/or prices, in email - if not here - on the cam, your pcm and the heads you have on order. I am curious, and was looking at the same mods.