# Engine self-destruct



## GraySkies (Feb 6, 2018)

My 2016 LT started suddenly running really rough while I was on the freeway last Thursday. I happened to have driven by the Chevy dealership just a few minutes before that, so I got off the freeway and took it straight there. It was not overheating or exhibiting any other symptoms other than the rough-running condition.

Talked to them today, and the said that it needs an entirely new engine. It's still under warranty, so I guess I'm not out much (they are giving me a loaner in the meantime), but it's a little disconcerting to find that a car with 40k miles on it needs a new engine already.

I am going in there tomorrow morning to talk to the tech and find out exactly what he found in there. 

Anyone have a similar experience, or know of a particular issue with these that I might have stumbled into? 

Please reassure me that I haven't made a mistake coming back to Chevy after a 17-year hiatus... 

I will report back after I have talked to the technician at the dealer tomorrow.


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## llbanks522 (Nov 23, 2017)

GraySkies said:


> My 2016 LT started suddenly running really rough while I was on the freeway last Thursday. I happened to have driven by the Chevy dealership just a few minutes before that, so I got off the freeway and took it straight there. It was not overheating or exhibiting any other symptoms other than the rough-running condition.
> 
> Talked to them today, and the said that it needs an entirely new engine. It's still under warranty, so I guess I'm not out much (they are giving me a loaner in the meantime), but it's a little disconcerting to find that a car with 40k miles on it needs a new engine already.
> 
> ...


Wow, really sorry to hear that! What octane gas have you been running during the 40K? Good luck on the repairs and let us know your outcome.


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## jblackburn (Apr 14, 2012)

Gen 2's have had issues with pistons cracking from LSPI. GM has redesigned the piston & has generally been just replacing those; although if the cylinder wall is scored from the bad pistons, the whole motor is replaced.

In the future, run a GOOD synthetic oil, run higher octane fuel (not 87), and try to avoid lugging it around down low.


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## GraySkies (Feb 6, 2018)

jblackburn said:


> Gen 2's have had issues with pistons cracking from LSPI. GM has redesigned the piston & has generally been just replacing those; although if the cylinder wall is scored from the bad pistons, the whole motor is replaced.
> 
> In the future, run a GOOD synthetic oil, run higher octane fuel (not 87), and try to avoid lugging it around down low.


Talked to the technician this morning. This is apparently exactly what has happened. The piston cracked in cylinder #1, and scored the cylinder wall. They are replacing the engine. 

I already use good synthetic oil that meets the proper Dexos standard, but I have not consistently used premium gas. So, JBlackburn, do you think it would be a good preventive measure to start using it with the new engine? I never used it before, because I was told that it was okay to use regular 87 octane in it. I have never heard that "pinging" sound you could hear in older cars when it was having issues, but I guess it wouldn't make the same sound in these, is that correct?

At least I got a 2017 "RS" for a loaner. Premium audio, heated seats, nicer wheels/tires and handling package... I might not want to give it back!


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## jblackburn (Apr 14, 2012)

GraySkies said:


> Talked to the technician this morning. This is apparently exactly what has happened. The piston cracked in cylinder #1, and scored the cylinder wall. They are replacing the engine.
> 
> I already use good synthetic oil that meets the proper Dexos standard, but I have not consistently used premium gas. So, JBlackburn, do you think it would be a good preventive measure to start using it with the new engine? I never used it before, because I was told that it was okay to use regular 87 octane in it. I have never heard that "pinging" sound you could hear in older cars when it was having issues, but I guess it wouldn't make the same sound in these, is that correct?
> 
> At least I got a 2017 "RS" for a loaner. Premium audio, heated seats, nicer wheels/tires and handling package... I might not want to give it back!


That's my plan. Any time I've switched down an octane grade, I hate the way my car runs. It has this WEIRD hiccup after you accelerate - even still in 6th and then level off on the gas (like in highway driving to switch lanes). Low-end power is a bit lacking on lower octane grades as well; it needs to drop gears more often.

Shouldn't ever hear audible pinging in a modern car, but I think the times I've heard LSPI events, I heard a rattling, a cough, and then suddenly the car pulled all power before I could even realize what was going on. I was moderately hard into the throttle between 2500-3500 RPM, running Dexos-1 dealer oil, and 87-89 octane both times.

Ask them if you can just keep the loaner at a discount


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## GraySkies (Feb 6, 2018)

jblackburn said:


> Any time I've switched down an octane grade, I hate the way my car runs. It has this WEIRD hiccup after you accelerate -
> 
> I think the times I've heard LSPI events, I heard a rattling, a cough, and then suddenly the car pulled all power before I could even realize what was going on. I was moderately hard into the throttle between 2500-3500 RPM, running Dexos-1 dealer oil, and 87-89 octane both times.


Don't think I recall ever experiencing anything like this. I don't drive it very aggressively, so maybe it has had the LSPI issue and the computer caught it before I noticed. It handles like such a pig anyway, I usually just drive it like a grandma...

I was driving an Audi A4 before I got this, and the letdown was pretty crushing. Sucked the life out of my commute. Needed a new car at the time, though, and wanted to downsize and go "economy" while the kids are in college. Hope it ends up truly being an economy move, and not a money-pit lemon.


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## Celdwist (Nov 17, 2016)

jblackburn said:


> That's my plan. Any time I've switched down an octane grade, I hate the way my car runs. It has this WEIRD hiccup after you accelerate - even still in 6th and then level off on the gas (like in highway driving to switch lanes). Low-end power is a bit lacking on lower octane grades as well; it needs to drop gears more often.
> 
> Shouldn't ever hear audible pinging in a modern car, but I think the times I've heard LSPI events, I heard a rattling, a cough, and then suddenly the car pulled all power before I could even realize what was going on. I was moderately hard into the throttle between 2500-3500 RPM, running Dexos-1 dealer oil, and 87-89 octane both times.
> 
> Ask them if you can just keep the loaner at a discount



I run premium in mine once I heard about the LSPI. I have been running it with 87 ever since I got the car, 18,000 miles of 87. And since it occurs in low RPMs, would it be best to just paddle shift when it gets hilly, shifting down into a lower gear to get more torque and higher rpms? I've been doing this and just keeping it in 4th gear around 3,000 to 3,400 RPMs. Or on the highway, shifting out of 6th and going into 5th to pass someone.


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## GraySkies (Feb 6, 2018)

jblackburn said:


> Gen 2's have had issues with pistons cracking from LSPI. GM has redesigned the piston


Do you think there is a pretty good chance the new engine will have the re-designed pistons? 

Do you think they can/will tell me if I ask?


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## jblackburn (Apr 14, 2012)

GraySkies said:


> Do you think there is a pretty good chance the new engine will have the re-designed pistons?
> 
> Do you think they can/will tell me if I ask?


One would hope. Yeah, wouldn't hurt to ask.


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## jblackburn (Apr 14, 2012)

Celdwist said:


> I run premium in mine once I heard about the LSPI. I have been running it with 87 ever since I got the car, 18,000 miles of 87. And since it occurs in low RPMs, would it be best to just paddle shift when it gets hilly, shifting down into a lower gear to get more torque and higher rpms? I've been doing this and just keeping it in 4th gear around 3,000 to 3,400 RPMs. Or on the highway, shifting out of 6th and going into 5th to pass someone.


One one hand, if mine's going to blow up, I hope it does it inside the warranty period. On the other hand, I'm hoping it won't because major engine work usually involves headaches (leaks, incorrectly installed things, etc) and I don't know that I'd want to own a car I'm still making payments on with those issues. 

A good prod of the gas will usually get a downshift out of it. Beyond that, I'm not going to drive it in any special way or tell the automatic what to do myself. Modern turbo motors are designed to have a flat torque curve from sometimes 1500 RPM on up, and that's one of the reasons I like them. GM's should be able to do that without blowing up pistons.


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## snowwy66 (Nov 5, 2017)

It's a tough call with these small engines these days. 

My motorcycle engine is 200 cc's bigger then my car. 1600 compared to 1400. And the 1400 car engine has 3 times more horse power.


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## jblackburn (Apr 14, 2012)

snowwy66 said:


> It's a tough call with these small engines these days.
> 
> My motorcycle engine is 200 cc's bigger then my car. 1600 compared to 1400. And the 1400 car engine has 3 times more horse power.


80s throttle body injected V8s were making less HP than these 1.4s 

Sent from my SM-G950U using Tapatalk


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## 17Cruzer (Apr 18, 2017)

GraySkies said:


> Do you think there is a pretty good chance the new engine will have the re-designed pistons?
> 
> Do you think they can/will tell me if I ask?


I would love to see a data log showing boost, lambda, ignition, and knock.


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## GraySkies (Feb 6, 2018)

17Cruzer said:


> I would love to see a data log showing boost, lambda, ignition, and knock.


What kind of gear do you have to have to log those things? I only have a generic code reader. I own neither a laptop nor a smartphone.


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## GraySkies (Feb 6, 2018)

Found out this evening that the new engine is supposed to arrive tomorrow. They said I will have my car back by next Wednesday. I guess we'll see.


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## quailallstar (Feb 16, 2018)

Best of luck. Hope it all works out. 

Sent from my SM-G965U using Tapatalk


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## GraySkies (Feb 6, 2018)

Actually, the thing that is bugging me the most in all this is that I was getting ready to do a major stereo upgrade, and now I've been having to wait. I have all the stuff sitting on the bench in the garage, waiting for the car to come home.


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## obermd (Mar 3, 2012)

GraySkies said:


> Actually, the thing that is bugging me the most in all this is that I was getting ready to do a major stereo upgrade, and now I've been having to wait. I have all the stuff sitting on the bench in the garage, waiting for the car to come home.


Be glad it did it before you upgraded the stereo. Some dealerships would try to use the upgraded stereo to void the powertrain warranty, even though pistons are a known issue.


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## GraySkies (Feb 6, 2018)

obermd said:


> Be glad it did it before you upgraded the stereo. Some dealerships would try to use the upgraded stereo to void the powertrain warranty, even though pistons are a known issue.


I suppose they could try that, if they thought it would cost less to defend a lawsuit than to honor the warranty. This is a well-known enough problem now that I am surprised no enterprising ambulance-chaser attorney has given the class-action thing a whirl on it...


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## 17Cruzer (Apr 18, 2017)

jblackburn said:


> Gen 2's have had issues with pistons cracking from LSPI. GM has redesigned the piston & has generally been just replacing those; although if the cylinder wall is scored from the bad pistons, the whole motor is replaced.
> 
> In the future, run a GOOD synthetic oil, run higher octane fuel (not 87), and try to avoid lugging it around down low.


Good point regarding LSPI. 

More info on LSPI:

https://www.oronite.com/products/lspi.asp

https://www.motor.com/magazine-summary/resolving-low-speed-pre-ignition/

Makes for a good reason to add a catch can, use L6 to avoid auto start/stop, use 93 octane fuel, and don't lug the engine, shift to a lower gear.


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## GraySkies (Feb 6, 2018)

Engine arrived, but they said they are still waiting on some of the small parts and gaskets. Now looking like I won't get this back until next week. Oh, well. I guess I'll "live with" my 2017 RS loaner for another week... :biggrin:


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## 17Cruzer (Apr 18, 2017)

GraySkies said:


> What kind of gear do you have to have to log those things? I only have a generic code reader. I own neither a laptop nor a smartphone.


If MoTeC supported Cruze tuning, I have an M130 with I2 datalogging. I'm currently using it in a different application.


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## obermd (Mar 3, 2012)

GraySkies said:


> Engine arrived, but they said they are still waiting on some of the small parts and gaskets. Now looking like I won't get this back until next week. Oh, well. I guess I'll "live with" my 2017 RS loaner for another week... :biggrin:


This is actually a good sign you have a good dealership. They don't want to put the old, worn parts and gaskets back in, which are more likely to lead to further problems down the road.


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## GraySkies (Feb 6, 2018)

Apparently they got the rest of the parts in, and finished the job. Got the call this morning. Just picked it up.

The new engine has a 3 year/100k warranty. I will continue to use the good oil, and will start using premium gas all the time. 

Some have suggested that the auto stop/start might have something to do with it. I'm not so sure about that. Do any of you have any information that might be helpful? I've read about some people driving in L6 all the time, to defeat this feature...

Mileage is one of the main reasons I bought this car, so going to premium gas already kinda hurts. I don't want to start dropping mileage enhancing features also...


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## snowwy66 (Nov 5, 2017)

There have been a number of scenarios floating around. 

From a computer tune, to auto/stop, to low rpms, to advanced timing, to octane. TAke your pick. 

What I've seen mostly is low octane but the low rpms could be a possibility and advanced timing if that's the case. 

Others have had their cruze's longer and have seem more stories. So they might have same or other ideas. 

I don't think there's been a public service announcement so it's really anyone's guess.


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## jblackburn (Apr 14, 2012)

GraySkies said:


> Apparently they got the rest of the parts in, and finished the job. Got the call this morning. Just picked it up.
> 
> The new engine has a 3 year/100k warranty. I will continue to use the good oil, and will start using premium gas all the time.
> 
> ...


Happened to enough manual transmission ones that I doubt it has a thing to do with start/stop.

People do love to hate that "feature", though.


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## GraySkies (Feb 6, 2018)

jblackburn said:


> Happened to enough manual transmission ones that I doubt it has a thing to do with start/stop.
> 
> People do love to hate that "feature", though.


I have been at a bit of a loss to understand why. It operates pretty darned seamlessly for me, and most of the time it doesn't really even register with me anymore that the car has shut off when stopping. It shuts off a lot less with the AC on, and doesn't seem to shut off at all when the defroster is on, so what's the big deal?

Even when I am going in a hurry (like turning left across traffic), the starter always beats my foot from the brake to the gas...


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## rry3158652 (Jan 23, 2018)

I agree with previous post. Auto start/stop does not seem to be that big of an issue to me.


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## snowwy66 (Nov 5, 2017)

jblackburn said:


> Happened to enough manual transmission ones that I doubt it has a thing to do with start/stop.
> 
> People do love to hate that "feature", though.


I gave it 5 weeks of warm weather. Decided i didn't want to live with it. And the L6 thing was getting on my nerves. 

There's more involved then just the standard stop light. Like others have mentioned. It shuts off and starts back up when parking. If you're not fast enough. 
I"m only stopped for 2 seconds. Not worth the wear and tear for such a short savings of clean air. Specially come summer time. 

Different strokes for different folks. I don't want the wear and tear on starter and flywheel or the risk of having the system fail in rush hour traffic at a stop light. 

I gave it a shot. I just didn't like or want it. So i did away with it. And I"m really loving the transmission again. The way a transmission USED to operate before the days of engine lugging.

:smile:


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## llbanks522 (Nov 23, 2017)

GraySkies said:


> Some have suggested that the auto stop/start might have something to do with it. I'm not so sure about that. Do any of you have any information that might be helpful? I've read about some people driving in L6 all the time, to defeat this feature...
> 
> Mileage is one of the main reasons I bought this car, so going to premium gas already kinda hurts. I don't want to start dropping mileage enhancing features also...


I drive in L6 all the time. IDK perhaps something is not right with my 2017 LT or I’m just to sensitive to the off/on engine jump of The AS/S. IMO it is not seamless and I don’t know what the long term wear and tear will be on the starter, transmission, and engine, only time will tell. I would get a “Tune” and spend some $$ to defeat the AS/S if it wasn’t for the fact that you run the risk losing your warranty coverage on the power train if a major problem occurs and the dealership sees that the ECM was flashed with a tune. Rest assured that they would deny warranty coverage and you would be the one to have to prove to GM that they are wrong. (Good luck with that).


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## GraySkies (Feb 6, 2018)

llbanks522 said:


> I don’t know what the long term wear and tear will be on the starter, transmission, and engine, only time will tell.


I guess I will end up being one of the lab rats for finding out! hmy:

This "feature" is new enough that I don't think anyone really knows what the long-term effects will be. I did some reading up on this setup after test-driving the car, and they did invest significant engineering time into redesigning the starters for a cycle life 10x greater or more, and engine bearings that have different lubrication properties and oiling system and such. Seems like it's not something they just slapped together. I guess we'll see. 

It's not something I am apprehensive enough about to go through a bunch of work-around gyrations to bypass it in my normal driving, and I have no plans to ever get a tune in this thing. Like I said, I guess I'm volunteering to be a lab rat... :wink:


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## snowwy66 (Nov 5, 2017)

One gal has already posted on here of getting a new flywheel and starter. 

As for the tune. Looks like it adds a program to run along side the original program. It runs when the cruise is off. Turn on the cruise and the stock program runs. It doesn't actually flash the entire computer. It certainly don't trigger the counter. Any problems, you simply delete the tune side of it. STock one remains. Dealer won't know. I could be wrong but that's what it looks like. And the tunes are advertised as NOT triggering the counter. 

As for warranty problem. It's happened on both tuned and non tuned vehicles. 

I think the denial would be whether there's evidence of tampering. Go in with evidence and you're certain to be denied. Like the 1 guy who had a tune and exhaust posted on youtube.
There's also one guy posted on here. He works for Chevrolet. He had an aftermarket air intake system. I don't think anything was posted as to his warranty.

I think if it came down to a fight, though. One could certainly make an argument. As enough people have posted that have done nothing to their cars. But drive them.


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## grs1961 (Oct 23, 2012)

GraySkies said:


> ...
> This "feature" is new enough


It's not *new* in the rest of the world, it's really quite common, it's more that the USA is lagging behind.


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## Premier17 (May 20, 2017)

snowwy66 said:


> One gal has already posted on here of getting a new flywheel and starter.
> 
> As for the tune. Looks like it adds a program to run along side the original program. It runs when the cruise is off. Turn on the cruise and the stock program runs. It doesn't actually flash the entire computer. It certainly don't trigger the counter. Any problems, you simply delete the tune side of it. STock one remains. Dealer won't know. I could be wrong but that's what it looks like. And the tunes are advertised as NOT triggering the counter.
> 
> ...


I have to somewhat disagree with you here. The reason being, I also have the Trifecta tune, and when I originally got the tune I had some big issues when the cruise was on and it was in "stock" mode where the car could barely accelerate. (0-60 times were like 16 seconds!) I don't want to drone on and get into needless details, but they quickly fixed the tune, and the new does not have this issue. BUT what this tells me is that it completely over writes the factory tune, even in "stock" mode.


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## jblackburn (Apr 14, 2012)

Premier17 said:


> I have to somewhat disagree with you here. The reason being, I also have the Trifecta tune, and when I originally got the tune I had some big issues when the cruise was on and it was in "stock" mode where the car could barely accelerate. (0-60 times were like 16 seconds!) I don't want to drone on and get into needless details, but they quickly fixed the tune, and the new does not have this issue. BUT what this tells me is that it completely over writes the factory tune, even in "stock" mode.


Right; it is typically LIKE the factory calibration in "normal" mode, but it does overwrite the factory calibration when the tune is installed.


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## snowwy66 (Nov 5, 2017)

The setup app shows 2. Where before there was only 1. Mirrored copy? And wouldn't it reboot for a full on flash?


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## GraySkies (Feb 6, 2018)

Hey Premier17, how has the Trifecta tune affected your overall fuel mileage?


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## snowwy66 (Nov 5, 2017)

Premier17 said:


> I have to somewhat disagree with you here. The reason being, I also have the Trifecta tune, and when I originally got the tune I had some big issues when the cruise was on and it was in "stock" mode where the car could barely accelerate. (0-60 times were like 16 seconds!) I don't want to drone on and get into needless details, but they quickly fixed the tune, and the new does not have this issue. BUT what this tells me is that it completely over writes the factory tune, even in "stock" mode.


I was under the impression it wrote it's own program. OR mirrored the original with changes written. 

The setup app looks like there's 2. Like having a dual operating system computer. When there was only 1 before. 

Having 2 programs would make sense since it can be changed with the cruise button. I"m not seeing how it can be done any other way. But I'm not a coder. And I haven't even played with my cruise to see if the car still works in that mode. Other then to see the engine stop and restart at a stop light with the push of the cruise button.


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## 17Cruzer (Apr 18, 2017)

jblackburn said:


> Happened to enough manual transmission ones that I doubt it has a thing to do with start/stop.
> 
> People do love to hate that "feature", though.


Turbos love some idle time to cool the center section. AS/S doesn't allow a cool off. Perhaps some oil by-passes the bearing seals and upon start up.....eats a piston.


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## jblackburn (Apr 14, 2012)

17Cruzer said:


> Turbos love some idle time to cool the center section. AS/S doesn't allow a cool off. Perhaps some oil by-passes the bearing seals and upon start up.....eats a piston.


I've owned turbo cars for the past 12 years and never idled one before shutting it off. 

Sent from my SM-G950U using Tapatalk


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## 17Cruzer (Apr 18, 2017)

jblackburn said:


> I've owned turbo cars for the past 12 years and never idled one before shutting it off.
> 
> Sent from my SM-G950U using Tapatalk


No offense, but that doesn't mean anything. My GXP doesn't exhibit LSPI, and I idle it for about 1 minute before shut down, same for my Duramax.


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## amouly (Sep 17, 2017)

17Cruzer said:


> Turbos love some idle time to cool the center section. AS/S doesn't allow a cool off. Perhaps some oil by-passes the bearing seals and upon start up.....eats a piston.


Auto star/stop doesn't matter for the turbo. When the engine stops, the oil reflow it's closed and the oil is not going back to the carter deposit. That means the oil still cooling the turbo center section. That's how this engine protects the turbo and avoids this one to spin without oil.


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## Premier17 (May 20, 2017)

GraySkies said:


> Hey Premier17, how has the Trifecta tune affected your overall fuel mileage?


Honestly I haven't really noticed any difference in fuel economy VS stock and I drive it in the "tuned" mode almost exclusively. The only time I throw it into stock is at a red light and I want the auto-stop to kick in. (LOVE having the ability to control when it's enabled!!) On the highway I still average right around 40 MPG and in my mixed driving of 60% city and 40% highway I'm averaging about 33.


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## Mbz300sdl (Jan 6, 2018)

jblackburn said:


> That's my plan. Any time I've switched down an octane grade, I hate the way my car runs. It has this WEIRD hiccup after you accelerate - even still in 6th and then level off on the gas (like in highway driving to switch lanes). Low-end power is a bit lacking on lower octane grades as well; it needs to drop gears more often.
> 
> Shouldn't ever hear audible pinging in a modern car, but I think the times I've heard LSPI events, I heard a rattling, a cough, and then suddenly the car pulled all power before I could even realize what was going on. I was moderately hard into the throttle between 2500-3500 RPM, running Dexos-1 dealer oil, and 87-89 octane both times.
> 
> Ask them if you can just keep the loaner at a discount


 I bought my '17 Premier back in Jan with 18K miles on it it now has 23K on it and I have ran it in L6, 93 octane and has Mobil one Dexos GM approved oil.

It sometimes has that same kinda hiccup or what I would call hesitation though I don't hear the rattling. It is rather annoying when you need to merge into traffic then the car decides nope not this moment but it has also done it while slowing pulling away from stop sign on my road. I do run it fairly hard when needed but don't see why this would, could, or should be an issue in a modern car.


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## GraySkies (Feb 6, 2018)

Where do you guys get 93 octane gas? 91 is the highest I can find anywhere in my area, except at the racetrack.


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## snowwy66 (Nov 5, 2017)

Some states sell 93. 

Mine only sells 91. But i used to know of a motorcycle shop that sells 130 aviation fuel. I don't know if they still sell it. And i don't know if it's actual aviation fuel. But that's what they called it.


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## 17Cruzer (Apr 18, 2017)

amouly said:


> Auto star/stop doesn't matter for the turbo. When the engine stops, the oil reflow it's closed and the oil is not going back to the carter deposit. That means the oil still cooling the turbo center section. That's how this engine protects the turbo and avoids this one to spin without oil.


In review, I said....."Perhaps some oil by-passes the bearing seals upon start up". There are 4 possible ways oil could end up in the combustion chamber (LSPI):
bypassing the ring package, bypassing the guides/seals, PVC, turbo bearing seals. When a hot turbo is shut down without cool off, there is no cooling of the turbo via oil and/or water as there is no oil and/or water circulating to the bearing/shaft. Thankfully, todays oils resist "coking". Still, heat could push a very very small amount of oil pass the seals, into the intake track/IC and subsequently into the combustion chamber. I'm not saying this is fact, just that its possible. ​


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## Barry Allen (Apr 18, 2018)

snowwy66 said:


> Some states sell 93.
> 
> Mine only sells 91. But i used to know of a motorcycle shop that sells 130 aviation fuel. I don't know if they still sell it. And i don't know if it's actual aviation fuel. But that's what they called it.


AV gas is useless in anything other than aviation engines. It's not enough to have a high octane rating as fuels have other criteria such as flame speed that are important for high-revving (motorcycle) engines. AV gas is designed for large bore, slow-revving engines that were the height of engine technology in the 1930s.

I have used AV gas in a motorcycle I owned, but that's because it called for leaded fuel. I'd use one tank of leaded AV gas about every 4th tank of fuel through the bike, and that was enough to coat the exhaust valves with lead. Other than that, it was useless fuel for any purpose other than aircraft engines.


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## AuditorBill (Jan 6, 2017)

I put 93 in my '17 (built Dec. '16) for a several-hundred-mile trip last weekend, but last summer used 89. I'll use 89 this summer, but this is irritating in a car that is supposed to run on 87 and with gas prices doing what they're doing now. (I use 87 the rest of the year in cold/cool weather.)

I have to say, I grew up loving Chevrolets; my Dad and grandfather drove them; loved new-car introduction night at the Chevy dealer and trying to spy the new models before introduction time; have owned 14 new Chevrolets and five used since 1981, but my faith is fading. Between what these cars are doing and what Equinox 2.4's (bought one of those for daughter) are doing, widespread, someone should feel ashamed at GM. Somehow, I doubt it though. Terrible wondering when this huge stuff is going to happen on our cars.


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## Celdwist (Nov 17, 2016)

AuditorBill said:


> I put 93 in my '17 (built Dec. '16) for a several-hundred-mile trip last weekend, but last summer used 89. I'll use 89 this summer, but this is irritating in a car that is supposed to run on 87 and with gas prices doing what they're doing now. (I use 87 the rest of the year in cold/cool weather.)
> 
> I have to say, I grew up loving Chevrolets; my Dad and grandfather drove them; loved new-car introduction night at the Chevy dealer and trying to spy the new models before introduction time; have owned 14 new Chevrolets and five used since 1981, but my faith is fading. Between what these cars are doing and what Equinox 2.4's (bought one of those for daughter) are doing, widespread, someone should feel ashamed at GM. Somehow, I doubt it though. Terrible wondering when this huge stuff is going to happen on our cars.



I run mine only with 93, though I have been using 87 ever since around 17 or 18K miles when I learned about the LSPI. I'm at 19642 miles now, no problems, I even have a muffler delete but thinking about welding the stock muffler back on and probably selling the car. I don't want to run into these issues down the road.


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## Barry Allen (Apr 18, 2018)

AuditorBill said:


> this is irritating in a car that is supposed to run on 87


I realize many people buying many brands have fallen for a sales pitch, but there are zero situations with turbocharged engines that it is acceptable to use regular gasoline. With 87 octane fuel the ECU is running the mixture rich and retarding timing so much that it's robbing the car of performance potential and it's impacting fuel economy. Everyone who owns a turbocharged gasoline Cruze should consider 89 octane to be the absolute minimum fuel spec, and in hot weather it should be bumped up to 91 octane.


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## SilverCruzer (Nov 30, 2010)

Barry Allen said:


> I realize many people buying many brands have fallen for a sales pitch, but there are zero situations with turbocharged engines that it is acceptable to use regular gasoline. With 87 octane fuel the ECU is running the mixture rich and retarding timing so much that it's robbing the car of performance potential and it's impacting fuel economy. Everyone who owns a turbocharged gasoline Cruze should consider 89 octane to be the absolute minimum fuel spec, and in hot weather it should be bumped up to 91 octane.


Well....I very easily get 44 MPG on my commute both ways to work on 87 gas. I believe that to easily fall into the fuel spec of the design. I tried 89 for a bit and did not do better and even if I did, the price premium would have blown away any cost on fuel savings.
Performance? Merging on the freeway from 30 to 70 works just fine.


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## alanl11 (Apr 8, 2018)

snowwy66 said:


> One gal has already posted on here of getting a new flywheel and starter.
> 
> As for the tune. Looks like it adds a program to run along side the original program. It runs when the cruise is off. Turn on the cruise and the stock program runs. It doesn't actually flash the entire computer. It certainly don't trigger the counter. Any problems, you simply delete the tune side of it. STock one remains. Dealer won't know. I could be wrong but that's what it looks like. And the tunes are advertised as NOT triggering the counter.
> 
> ...


I don't think Trifecta tunes install along side, they will give you an stock tune with theirs to go back to. The problem is I've learned that the ECM has a write counter and every time it's flashed it counts. Every time a GM dealer flashes your ECM it's documented and logged. If you come in with an major warranty claim GM will insist the techs check and compare your flash count. If it doesn't match their records you are denied warranty. Even putting back stock.


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## snowwy66 (Nov 5, 2017)

That's allright. 

The lack of cold misfire
The increased horsepower
The improved fuel mileage
The lack of engine lugging
The lack of autostop

It's nice to have a car again. The way a car used to be. With some added pep. And economy that can compete with the imports.

Best money I've ever spent on a car.


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## alanl11 (Apr 8, 2018)

alanl11 said:


> I don't think Trifecta tunes install along side, they will give you an stock tune with theirs to go back to. The problem is I've learned that the ECM has a write counter and every time it's flashed it counts. Every time a GM dealer flashes your ECM it's documented and logged. If you come in with an major warranty claim GM will insist the techs check and compare your flash count. If it doesn't match their records you are denied warranty. Even putting back stock.


Trifecta told me that their tune "replaces" the stock tune but that their tune won't trigger the write count on the ECM using transparency mode?


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## ccawley02 (Jan 12, 2020)

Hi... my first post. Recently purchased a 2017 Cruze from a GM dealership, with 46K on the odo. Drove it to upstate NY and back over the holidays, plus other driving, now just a shade under 50K miles. I've been using 87 octane, but after reading this thread I will immediately switch to either 89 or 93 going forward. Driving 1900 miles over the holidays, 90% interstates, but a fair bit of bouncing around towns, and got 43 mpg for the trip. On 87 octane.

(Oddly enough I had traded in a 2000 Sable that had crazy pinging/"spark knock" if I used anything other than 93 octane... and even then I would get knock under load. The old Ford Vulcan engine.)

I ran a carfax on the Cruze, and it was a leased vehicle prior to my owning it, other than getting regular oil changes and a minor fender-bender in NYC, there are no other records listed. I have no clue what kind of oil has been used, or fuel grade, prior to my owning it. 

FWIW The VIN has a date code H (2017), and the production # is 145871. At least that's how I read the VIN code.

I purchased a 3-year, 36,000 mile bumper-to-bumper warranty with the car, so I guess I'm "good" if the engine blows up. I'm hoping, though, that the window for that happening would be closed by now since it's pushing 50K miles.... one of those cases of "if it's gonna happen, it would have happened by now"....??? 

Definitely keeping all this info handy in the event it DOES happen and the dealership wants to give me issues. 

I'm sorry... really sorry... that yall had these issues. I am grateful, though, that I found this form and the information.


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## WillL84 (Aug 5, 2019)

I bought a 2017 in August with only 6k on it. Pushing 11k now. Glad that the powertrain warranty is 5 years!


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## MyChevy (Jan 10, 2020)

2016 Cruze I bought brand new, always use synthetic, always use 87, octane, 80,000 miles no engine issues other than a code that was caused by someone not tightening the air cleaner screws.


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## Farmerboy (Sep 2, 2012)

I really think oil quality has more to do with LSPI than octane. GM dexos is very liberal in it’s allowances. Using better oil that beats dexos and allows no LSPI. My 2 bits.


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## WillL84 (Aug 5, 2019)

Farmerboy said:


> I really think oil quality has more to do with LSPI than octane. GM dexos is very liberal in it’s allowances. Using better oil that beats dexos and allows no LSPI. My 2 bits.


That's why they have the dexos gen 2 now


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## PolarisX (Dec 17, 2017)

The only time I had an event (noise / power drop) was on 87 octane when I was running the tank of gas from the dealer. I went to merge onto a bypass road and the car just voted no. I had to back out of the throttle to get it back up again. Had a number of crackling noises and vibrations.

Never happened again, ran another 15k stock, and am now tuned.


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