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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
GM stopped the Dealership from any investigation of the motor. Literally the car has been evaluated based on my bringing the car in for oil consumption 2 years ago. zero effort to resolve, zero effort to diagnose.
2 years ago I reported heavy oil consumption.
Many tests of document oil consumption ensued
Results reported to GM
Results analyzed.- No valve covers pulled. Only real test was compression test.
GM Engineering stated "Normal oil of consumption for cars operated over 3k RPM" after 0 investigation.
fast forward 2 years
Car has consumed many quarts of oil in muddled silence of "normal LS7 operation" verdict
I start to notice blue smoke on start up in cold weather (new symptom)
GM Engineering re-engaged as symptom is now smoke on startup
No Tests Completed. No compression test, no wiggle, nothing.
GM proclaims the Z06 is normally driven "hard" (paraphrase) therefore this new issue is normal. ie 37k miles and blue smoke is normal in a commuter and weekend softball tournament car...
CUSTOMER STATES "WHEN STARTING VEHICLE THERE IS A PUFF OF BLUE SMOKE THAT COMES OUT THE TAILPIPE". CUSTOMER STATES THE SMOKE LEAVES A BLACK SPOT ON THE DRIVEWAY. CK AND ADVISE AS PER TAC PERFORMED VACUUM TEST ON ENGINE (PASSED). PERFORMED COMPRESSION TEST (PASSED), TECH CALLED TAC ASSISTANT BACK WHICH WAS THEN ESCALATED TO ENGINEERING. ENGINEER STATES AS PER LAST TAC CASE AND THIS VISIT ARE IDENTICAL ISSUES AND NOT TO DO ANYTHING WITH THE VEHICLE. WITH UPPER VALVE TRAIN NOISE AND SMOKE ON START UP SHOWS VEHICLE IS BEING DRIVEN AS WAS TOLD LAST VISIT. ENGINEERING STATES THIS IS A NORMAL CONDITION FOR AN ENGINE BEING RAN HARD TO HAVE THESE CONDITIONS.
Interesting that GM defaulted to "driven hard" when I daily drive it in traffic.
I would ask for their definition of being “ran hard” as well as trying to get an idea of what potential future issues may also be dismissed because of this assessment.
For example, if it drops a valve, or has a rocker let go, or spins a bearing, or has a damper start to wobble, Or experiences any other ailment that others have also had, would they dismiss for the same reason?
CUSTOMER STATES "WHEN STARTING VEHICLE THERE IS A PUFF OF BLUE SMOKE THAT COMES OUT THE TAILPIPE". CUSTOMER STATES THE SMOKE LEAVES A BLACK SPOT ON THE DRIVEWAY. CK AND ADVISE AS PER TAC PERFORMED VACUUM TEST ON ENGINE (PASSED). PERFORMED COMPRESSION TEST (PASSED), TECH CALLED TAC ASSISTANT BACK WHICH WAS THEN ESCALATED TO ENGINEERING. ENGINEER STATES AS PER LAST TAC CASE AND THIS VISIT ARE IDENTICAL ISSUES AND NOT TO DO ANYTHING WITH THE VEHICLE. WITH UPPER VALVE TRAIN NOISE AND SMOKE ON START UP SHOWS VEHICLE IS BEING DRIVEN AS WAS TOLD LAST VISIT. ENGINEERING STATES THIS IS A NORMAL CONDITION FOR AN ENGINE BEING RAN HARD TO HAVE THESE CONDITIONS.
Interesting that GM defaulted to "driven hard" when I daily drive it in traffic.
..and another perfect example of why in the majority of cases it's a complete waste of time dealing with dealership services.
Your valves could be wildly out of spec and so long as the service engine light is off (sic), you are "good to go".
Last edited by Dan_the_C5_Man; 01-04-2019 at 04:53 PM.
I talk to Tony from Tony's Corvette tomorrow to see what are my options - he is an authorized service center for GMPP extended warranties in addition to the speed shop that did my header install on my last vette.
The update from the dealership is no update as of COB today. They will try again with Corvette engineering on Monday. (i am not holding my breath...)
Originally Posted by meridock
My warranty runs out next month... so they really don't care.
Then no time to waste! Get it over to you local GMPP authorized shop for an evaluation, and get that claim going. Make sure to have the guides evaluated regardless of the cause of this particular issue. I had my heads fixed under a GMPP claim at AHP, as they are an authorized GMPP repair center as well.
Already scheduled . Jan 26 I drop it off. Bad part is it is like 80 or 90 miles from my house...
So I asked what "driven hard" meant. So it seems like 2 years ago when I complained about oil consumption they observed black soot on the rear of the car. It is on that fact they term it "hard used". Imagine that ...it eats oil and I have soot. Talk about jumping to conclusions.
So I have the car at a local shop I favor that is also a GMPP warranty shop. When he started the car to move it to the lift he was immediately worried about the clatter from the motor. It was louder than ANY LS7 he had ever heard. The car now has a "do not start" sign on it.
Today he pulled the plugs and valve covers and immediately noticed 2 things. The picture of 4 plugs comes from the right hand bank. Please notice the fouling of the 2 plugs. Looks like someone substituted coal for electrode. the second thing he noticed was in between the valve springs. What you seen in the middle of the picture is a valve guide seal. Neither is a good sign for the motor. The next step is he has called GM to come out and look over his shoulder as he pulls the heads - he did open a new case with GM which is good for me as I think as I posted previously GM denies there is a problem and won't authorize a proper diagnosis. So for now the work is on my dime but I am more confident now that my car will actually be fixed by GM due to these initial findings.
I am seriously questioning the previous diagnostics. The dealership said they performed a compression test. Just how bad does a spark plug need to look before the technician will raise his hand and note his visuals to the GM engineer? I honestly question if the technician even pulled the plugs for the any testing.
Holy **** man. I agree with you there, if a tech DID in fact do a compression test, that would have been the first thing they see. Great call on getting this inspected, sounds like a decent shop you took it too as well. Further reaffirms I hate dealerships. Good luck man.
My shop reports we are good to go through the tear down to see if anything is in the motor and check the heads out formally. They met with the GM regional adjuster and he is on board with this. I currently see no issues with GMPP.
If you have a cracked/failed oil control ring it would not show up on a compression check as proper compression is a function of your upper and lower compression rings. It seems to be a common fallacy that oil consumption will always show up on compression tests.
In addition, if you have significant carbon buildup in the combustion chamber (as indicated by the fouled plug) that will elevate a compression check too.
Even though, the dealer should have pulled the plugs...
I bet you are leaking oil through your valve stem seals like crazy due to clearance issues. Happened here before and made thay whole cyl and plug BLACK.
I bet you are leaking oil through your valve stem seals like crazy due to clearance issues. Happened here before and made thay whole cyl and plug BLACK.
I think he has a lot more going on than guides 'n seals...
How the hell was the car even running with that plug in it?
I would take that **** up the flag pole with GM to how incompetent the other dealer was... really... they let that go and thought "oh no big deal"... im guessing, like you, that they did not do any of the work they said they did, yet still billed GM for it. GM should investigate that, but my guess is they will not.
01-03-2019, 09:29 PM
. Jan 26 I drop it off. Bad part is it is like 80 or 90 miles from my house...
