2017 Camaro SS LT1 Misfires - Dealer Can't/Won't Fix

Update:

The new dealer changed the plugs, cleared the codes and gave the car back. I'm fairly certain the issue was still present on the drive home, albeit (temporarily) improved. I might normally be irritated by their behavior, but I'm very relieved that I didn't have to pay for it. They also didn't know the history, so IMO their actions are not horrible. We have established the important precedent that the car has warranty and it should cover this issue. That's a big deal.

The comments from the tech suggest the car had a P0420/P0430 which I knew about. They also found P0172/P0175, which I couldn't see which is rich AFR on both banks. I'm not surprised, it's clear it's been running rich, but for some reason Torque won't show me the AFR. I'll drive it for a few days more days to get the plugs carboned up again and book another appointment.

If it comes back  again you may want to ask the service people  if the rich condition can damage the converters.  It would be even better if they document in there records that you asked this.  My fear is that if this keeps going on unfixed you are going to end up with cat damage.  If in the future there is cat damage found you obviously want those replaced under warranty due to the rich condition.  Dealer supplied cats are usually very expensive.

A special case technical guy I knew that use to fly around the country to look at cars that the dealers staff technicians could not figure out the problem told me that cats in cars do not die they are murdered by another problem/issue with the car.

Dean1484 - what you say makes a lot of sense. I have no doubt the cats are being negatively affected by the raw gas and backfires that are occurring. I suspect the P0420 code will come back.

I found some cats in junkyards online for a much more reasonable price than I expected. That said, the cats still have > 6.5 years of warranty. We'll see how things go with this issue and generally with the car in the next couple of years. I took over the lease with the expectation that I would buy it out at the end. The overall costs made a lot of sense. If this is more than particularly irritating one off issue, I may have to reconsider and just get rid of the car at the end fo the lease. Not many people sell a RX-8 and wish their new car was half as solid. ;)

May I ask....are you still enamored with this??......'Like I know it's all gonna be OK and the fun will begin again'...or are you thinkin' this effen sucks and I want JUSTICE?!?!?  Cuz my CTSV has not been the easiest  to 'dance' with?....and thru it all I'm not inclined to toss it (CTSV). 

just wonderin'.......

Snrub said:

Update:

The new dealer changed the plugs, cleared the codes and gave the car back. I'm fairly certain the issue was still present on the drive home, albeit (temporarily) improved. I might normally be irritated by their behavior, but I'm very relieved that I didn't have to pay for it. They also didn't know the history, so IMO their actions are not horrible. We have established the important precedent that the car has warranty and it should cover this issue. That's a big deal.

The comments from the tech suggest the car had a P0420/P0430 which I knew about. They also found P0172/P0175, which I couldn't see which is rich AFR on both banks. I'm not surprised, it's clear it's been running rich, but for some reason Torque won't show me the AFR. I'll drive it for a few days more days to get the plugs carboned up again and book another appointment.

"AFR" isn't a PID.  You watch the fuel trims.  If the engine is in fuel control, the actual air/fuel ratio is what it is supposed to be, but a 172 and/or 175 (besides being very rare faults to have) indicate that the computer has reached a threshold of compensation where something Just Ain't Right.  Most cars have the limit before throwing a lean or rich fault as a nice round number in the 25-45% combined (long-term plus short-term trim) range.

If you have wide band oxygen sensors, you won't see an "AFR" reading, you'll see either a current flow, or an equivalency ratio.  Fuel is so variable in composition that nobody thinks in terms of a hard air/fuel ratio, just lambda or equivalency ratios.  1.0 is 1.0 whether stoich for the given fuel in the rail is 14.7:1 or 14.2:1 or 10.3:1.  (And if the computer is in closed loop, that number will resolutely stay at 1.0 - which is why you watch the fuel trims)

Sounds like the dealer techs are treating the symptoms instead of fixing the problem.  Time to call GM corporate, or see if Knurled has some free time 

759NRNG - The fun almost never started. It's been nothing but stress driving a car that's damaging itself with no way to fix it. What's far worse is service that was screwing me over and potentially significantly devaluing the vehicle (potentially making the warranty void) by claiming that I ruined it. I've always owned fun cars to make my life better. This is not.

Knurled - thanks, good info!

06HHR - Yes I agree, I tried describing it to the last dealership as having a tire with a nail it in and "fixing" it by adding air. They completely disagreed. I'm giving the new dealership one more try before I get GM involved.

I would have involved GM a long time ago.  Why would you subject yourself to this level of stress on a new car with a warranty?

Agree with Zoo.  Especially if you already are encountering resistance with the new dealer. Waste no time!

Do not pass Go, Do not get stroked by the service department again.

Contact your regional Customer Service Rep, dealerships operate based on their CS rating. The squeaky wheel gets greased.

my personal opinion: they are not going to fix the car, they are going to buy him out of the lease

ZOO - The upside of involving GM could be much brighter, but the downside could be far worse.

bentwrench - Could you elaborate more on the CS rating?

mad_machine - At this point, I can't say I'd be against that. If anyone from Canada wants to beat them to the punch, you can have the cash incentive I received. We're talking base 2.0L kind of cost. :)

Snrub said:

ZOO - The upside of involving GM could be much brighter, but the downside could be far worse.

 

That's just paranoid. 

Snrub said:

ZOO - The upside of involving GM could be much brighter, but the downside could be far worse.

bentwrench - Could you elaborate more on the CS rating?

mad_machine - At this point, I can't say I'd be against that. If anyone from Canada wants to beat them to the punch, you can have the cash incentive I received. We're talking base 2.0L kind of cost. :)

I have read the entire thread. I don’t see how there could be a downside unless there is some sort of undisclosed modding that has been done that you are worried they will find evidence of.    They want you to be happy.  

mad_machine said:

my personal opinion: they are not going to fix the car, they are going to buy him out of the lease

OP is the SECOND owner/lessee of the car, no?

It does smell kinda fishy.

Da Boss bought a one year old Avalanche a while back, and it had a persistent very light misfire/stumble.  We could watch it on our scan tools (including a Tech II).  He went back and forth at the dealer, and they roamed around from replacing strange things like transmission mounts (?) and finally they said it was normal.

SVreX said:

Snrub said:

ZOO - The upside of involving GM could be much brighter, but the downside could be far worse.

 

That's just paranoid. 

Agree 100%. I can't believe throughout all this that GMNA hasn't been contacted yet.

Two visits to dealer.   Call GM

Close to lemon law in the US.

Update:

On dealer visit #4 (dealer 2, visit 2) they changed 3 injectors, 2 fuel pipes related to the injectors and all of the spark plugs again. They did a AFIT (active fuel injector test) and found 2 injectors outputting too much, 1 too little. They found P0300 (misfires), while torque and a cheapy standalone reader showed a P0430 (cat efficiency low). They swear there was no P0430, but we'll assume they're wrong. I don't get why I never see all the generic OBDII codes they see.

They sent the car home with misfires again. I started suspecting the problem was still occurring part way home and confirmed it after I arrived home and did a short drive with OBDII monitoring. All cylinders were showing misfires, but one of the cylinders with a new injector was particularly bad. At one point, it was actually the worst I've monitored ever on a single cylinder (didn't actively monitor in the past with a flashing CEL). I had 36 on the cylinder misfire current count and 42 on the historic count. I'm shocked that doesn't trigger an immediate CEL. I logged 98 seconds with a current misfire count on the same cylinder, 118 seconds another time before I turned the car off. Some long term fuel trims are above -20.

I spoke to the service manager, who was very apologetic and personally came out to my home to drive the car back in. While his people certainly didn't do right by me, he seems like he will.

At what point do you think a persistent misfires results in physical damage?

Snrub said:

At what point do you think a persistent misfires results in physical damage?

Three visits ago.

Seriously, how have you NOT called GM corporate yet?!? 

This is frustrating to watch. Please turn it over to GM.

Dude... imagine they actually somehow fix the car tomorrow.  Are you going to sleep soundly at night ever again with this car?  And if the engine blows up in three years what are you going to do?  

If you come to a group asking for advice, and 30 people tell you to call GM but you won't, then why keep updating the situation when it doesn't get solved?

I'm sorry if I'm being a dck here, but honestly it's a frustrating thread to read... 

Maybe they are giving him good rentals to "test" while they have his car. 

I hear you guys, I do. bcp2011, you make a fair point about why continue posting if I'm not going to take the advice.

Here' my perspective: I was literally dialing GM when the service manager called me back. What exactly do you think GM Corporate is going to do? They can bash in the dealership's head to fix it, but the service manager *seems* like he's going to do the right thing now. I agree GM can make someone do their job, but if someone is engaged and trying to do their job, what does GM's involvement do?

In terms of trusting the engine, I'm asking the question, because I have concerns. :) If anyone has thoughts as to whether this means real lasting damage, I'd be eager to hear them. I've never been in this situation before. Javelin's perspective is what I'm worried about.

I took over the lease with the intent of buying out the car at the end. That's what made the cost of ownership make sense to me, long term ownership. Leasing it and giving it up, did not. I'm definitely leaning that way now... 

Edit: I'm really mulling over your point. I'll give GM a call and see what they're willing to do. I really think it'll be nothing because the service manager is doing his job and I doubt they're going to care about my feelings on the engine, etc. I'm not going to disclose the dealer #1 bad gas thing, I think that muddies the waters if internal engine work is in the car's future. Unless they take me out of the lease (fat chance) or I get a new engine this situation will cost me thousands. Even at the end of the lease I'll have to buy a set of OEM runflats to turn in the car.

Called GM customer care. No obvious traction. They told me it was a leasing company issue even after I argued, etc. (WTF?) I was transferred/spoke to the gm finance lease people they said I needed to talk to someone else there, but there was no obvious reason they would be involved. I've told both parties I'm out thousands because I can't possibly buy out the vehicle and that I wanted either out of the lease, or a new engine. We'll see how this goes.

The other reason I'm posting is to make my story publicly available. I'm well aware GM vehicles are not the most reliable, but this is a cautionary tale and what it means to own such a vehicle.