jiba2day

I live in a very small town, I am their first C8 delivered. I don't believe the tech has much experience with this particular car, even less than the others. I'm going to a dealer that has sold over 50 C8s and has two techs, I'd rather have the car sit in my garage than be tinkered on by someone who may not the best.

jiba2day

BPHORSEGUY

The plant did not put 20 miles on it!!!

heisnuts

I think you made the right choice. I am sure the tech checked the simple stuff like loose wire, bad plug, etc., and once that was not the problem they threw their hands up. I am sure once you find a tech who has some experience with the car AND has a desire to diagnose the problem you should be fine.

edit - now that I see your invoice, I see I was on the right track. Cylinder 5 has a misfire to it and it does not seem to be plug related. That means a tech is going to need to spend some time tracing down if there is power getting to the #5 plug, or if so, what internally is causing the cylinder to misfire.

ZRWalll

Unfortunately GM is too busy filing lawsuits against their dealerships and doesn't have enough resources to put in a working quality control system or certify techs to work on their products.

The stupidity at GM amazes me every day. Every day you see new C8 Corvettes dropping dead left and right only after a handful of miles and yet GM is suing a Chevy dealership in Iowa for adding FCA products to their GM dealership since FCA cars "tarnishes" GM’s image. The dealership group in Iowa is simply trying to cut overhead and stay in business. Any corporation with a lick of sense would be a lot more worried about their crappy quality being a bigger "tarnishing" factor than having a Jeep sitting next to a Camaro.

GM could care less how it's dealerships screw over potential GM customers. But put a Jeep next to a Camaro and you'll feel the wrath of GM attorneys in a heart beat!

Everyday I get up and see another Found On Road Dead C8. Right now there are only a relatively small handful of C8's on the road and from what I'm seeing the failure rate is incredible. Most of the C8's are either being flipped or sitting in garages collecting dust. If Toyota had this kind of crap quality control you would see a Toyota sittig on the side of the road every block!

Here's another one I read about yesterday....

Wife and I took delivery on Friday. We drove the car for a short drive then parked it in the garage with a total of 72 miles. That's correct....72 miles in total.

On Saturday morning (9/12/2020) I went to start the vehicle and left it idle for around 5 to 10 minutes. It was at this time the engine began to bog down with an erratic idle... like the car wanted to stall. I put the car in reverse to see if it was just a rough idle and that is when several indicators became apparent including a check engine, check transmission and check emissions alerts were sent.

I immediately called the dealer and they sent a flatbed.

This kind of idiotic behavior by GM management explains why GM's stock price will never exceed its initial IPO back in 2010.

https://gmauthority.com/blog/2020/09...der-same-roof/

Got uid0

It would fall under contract law. I believe it is 3 days

Bobby J

Fix it and sell it for a profit instead of returning.

NY09C6

There is nothing special about troubleshooting a cylinder misfire in a c8. Exact same procedure as troubleshooting it in a 2020 GM pickup truck.

dpigguy

Get the GM rep in your area involved. If not responsive, contact engineering in BG. I had to do that on my C6 that threw codes several times in first few weeks of ownership. The BG folks were great and gave me several things to check before taking it in for service by dealer. Fixed issue myself with their suggestions. Even looked them up on a trip to BG and thanked them.

ClothSeats

I thought GM had a program whereby if a dealership wanted to sell C8 Corvettes, they had to commit to buying several tools, provide training to maintenance and sales people, etc. All of that should have made your tech qualified to service your car. I haven't heard much about that program lately, so maybe GM gave up on it and let any dealership sell Corvettes that wanted to.

Carl44

A misfiring cylinder causes slight variations in the rotational speed of the crankshaft. The engine control module (ECM) is able to detect these
variations by closely monitoring the crankshaft position sensor signal. The signals of the camshaft position sensors are used to determine which
cylinder is misfiring. If the ECM detects a misfire rate sufficient to cause emission levels to exceed mandated standards, DTC P0300ts. Under
certain driving conditions, a misfire rate can be high enough to cause the catalytic converter to overheat, possibly damaging the converter. The
malfunction indicator lamp (MIL) flashes when catalyst damaging misfire conditions are present and DTC P0300 set.
P0300
The control module K20detects a crankshaft rotation speed variation indicating a misfire rate sufficient to cause emissions levels to exceed a
predetermined value or a misfire rate high enough to cause catalyst damage.
P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308
The control module K20detects a crankshaft rotation speed variation indicating a single cylinder misfire rate sufficient to cause emissions levels to
exceed mandated standards.
Actions Taken When the DTC Sets
DTCs listed in the DTC Descriptor Category = Type B> DTC
Malfunction Indicator Lamp (MIL) = Flashing - During catalyst damaging misfire.

Actions Taken When the DTC Sets
DTCs listed in the DTC Descriptor Category = Type B> DTC
Malfunction Indicator Lamp (MIL) = Flashing - During catalyst damaging misfire.
Conditions for Clearing the DTC
DTCs listed in the DTC Descriptor Category = Type B> DTC
Diagnostic Aids
Verify the following conditions do not exist:
{ If equipped } Command the Cylinder Deactivation system On with a scan tool, then observe the misfire counters when commanding the
system Off. If the misfire counters are incrementing, inspect for a sticking valve lifter.
DTC P0300y set when there is a condition with the component circuits: B52 Heated Oxygen Sensor
High resistance in the circuits of the component may set DTC P0300–P0308tting the DTC for the component: Q17 Fuel Injector
If the condition is intermittent, wiggle the related wiring harnesses and connectors, with the ignition/vehicle on or engine running, while
monitoring the scan tool circuit status parameters for the component. The parameters will display if there is a condition with the circuit or a
connection.
from the service manual . carl

23/C8Z

KISS worked there. Although I would have used a new plug in place of old not swapped. God forbid there is a slight crack in ceramic part of plug if you tap it the wrong way for example.

Did he swap coil pack? Wire? There's a ton more but that's because he wasn't getting paid to do more than that. Chevy isn't paying to swap parts around to confirm if it leads nowhere. Thats what you fell victim to. The call was by shop foreman or service manager and said "wait until they call us back with instructions" then they can submit warranty claim with a case number.

USMMA96

The dealer might have a return policy/program/etc, but that would be dealer specific, there is no “contract law” that allows you to return a car within 3 days.

baron95

There is nothing Corvette-specific about diagnosing a misfire on an LT engine that is (in similar form) installed in way over 1M vehicles. Any Chevy dealership tech should have seen dozens of such cases.

I think the OP is taking a big risk taking the car out of the dealership and driving it home, then driving to a farther away dealer. If the engine is too rough to drive, then it should not be driven. If something more catastrophic happen GM may give you a hard time to cover it given that you decided to drive tens of additional miles with the problem.

Sometimes you just need to give the process a chance to work. When I had active exhaust problems with my C7 it took 2 weeks for the dealer tech and GM remote techs to figure it out. In the end it was fixed correctly.

The fact that the dealership tech could not solve it by himself is actually a good thing, as they will involve GM tech support, which will provider better expertise from the get go.

23/C8Z

Think about the unspent fuel in the oil. Think about the possibility of washing down that cylinder wall..

Not a good look.

JKU007FL

Also don't forget GM stupidity by making a deal with the fraudulent Nikola, Barra must go.

Phil1098

He quit early, just because the plug swap left the miss on #5, he should have just swapped the coil and wires with the next one over. It wouldn't have taken an extra 15 minutes.

Phil1098

This is 100% bullshit. Please list the cars (plural) that have quit in a few miles EVERY DAY since the first one delivered. You can't do it because it's not true.

ZRWalll

The Nikola scam keeps on getting more hilarious every day. GM was basically out scamed/marketed by Nikola. In this video, which was all it took for GM to join up with Nikola, the truck was actually pushed down the incline and then filmed. The company even admitted that the truck wasn't filmed driving under its own power! What kind of corporation signs a megabuck agreement without even actually inspecting the goods of the scam company it partners up with? Total lunacy! lol

Here's the link to the Nikola scam stock price boosting video:

moncal90

Not to derail this thread... but you do realize that GM did not put up any money (cash) or stock in that Nikola deal. Nikola gave up 2 Billion in common stock for access to GM's parts and supply network and still has to pay GM 700 million for productions costs. Nikola may still be a scam or dead end for whatever future GM had planned for this venture but it's at least a lower risk.