Cracked Piston in my 2014 GS AWD

[Van Hellion]

Bought my Regal GS with 25,000 on the odometer back in April 2015. Drove it rather modestly for the remainder of the year. From out of nowhere in December, it started running rough - really rough. I was working out of town for most of the year so around the holidays I took it in to get looked at. They told me (at the dealership I bought it at) that it had a cracked piston. They dug in deeper and there was scoring on the cylinder wall so they are replacing the engine. Pretty crazy.... it's under warranty, of course, but I was curious to know if anyone had a similar issue and do you know what caused it?

Here's a pic of the little rocket:

 

[HotZ28]

Did you use premium fuel (93+) since you owned it?

 

[stoopid]

Bought my Regal GS with 25,000 on the odometer back in April 2015. Drove it rather modestly for the remainder of the year. From out of nowhere in December, it started running rough - really rough. I was working out of town for most of the year so around the holidays I took it in to get looked at. They told me (at the dealership I bought it at) that it had a cracked piston. They dug in deeper and there was scoring on the cylinder wall so they are replacing the engine. Pretty crazy.... it's under warranty, of course, but I was curious to know if anyone had a similar issue and do you know what caused it?

Here's a pic of the little rocket:
View attachment 8599

There haven't been a lot of failures with the LTG engine, but when there has been cracked pistons has been one of the most common. Owners of the Cadillac ATS report them quite often.

I was researching whether to tune my Regal, and in my research found a couple issues popping up. What isn't determined is whether tuning plays any role. Supposedly not all the failures are on tuned vehicles.

One theory is that fluid (that's supposed to be vented) is making its way back to the top of the piston, causing pressure where there isn't supposed to be. If the piston was cracked at the very top (near the rings) then that would be identical to what I've read.

I posted some links/results of my findings in this thread: http://buickforums.com/forums/threads/39842-Tuning-2-0T-reliability-issues

 

[dmr02]

it's under warranty, of course, but I was curious to know if anyone had a similar issue and do you know what caused it?


I work at a dealer and I have yet to see a LTG Regal need a motor, keep us up to date when you find out what exactly caused it, perhaps the previous owner wasn't up to date with his oil changes etc, beauty GS by the way!

 

[kranz38]

It does happen, unfortunately. Could have been a badly seated ring that scored the cylinder and tore up the piston. Several possibilities; the stock pistons will not hold up to detonation for a long time either.

 

[Van Hellion]

Did you use premium fuel (93+) since you owned it?

No - I have not. Came on this forum and even asked at the dealership to confirm that I can use 87 and the consensus was "yes".

- - - Updated - - -

it's under warranty, of course, but I was curious to know if anyone had a similar issue and do you know what caused it?


I work at a dealer and I have yet to see a LTG Regal need a motor, keep us up to date when you find out what exactly caused it, perhaps the previous owner wasn't up to date with his oil changes etc, beauty GS by the way!

Thank you! I love that car - bummer to see it have to get a new engine but I guess, better now than down the road.

 

[Van Hellion]

I'm getting the feeling that the person that owned the car before me may have beat the snot out of it when he had it. That sucks.... but, again, I am getting the engine replaced under warranty for the price of..... on the house.

 

[stoopid]

No - I have not. Came on this forum and even asked at the dealership to confirm that I can use 87 and the consensus was "yes".

I think HotZ asked because you could get detonation with lower grades of fuel. The car's computer is supposed to mitigate this as much as possible, which is why it's acceptable to run 87 with the LTG (it just doesn't produce as much power as running it with 93 octane).

http://www.superchargersonline.com/index.php?main_page=page&id=46

Seeing that very few ATS owners with this problem are public about their driving habits and/or tuning status, I'd say you are probably correct in assuming the car's life prior to you taking ownership was spirited. There's even a few Regal owners among us that like to push things with the LTG. 😉

 

[TRIFECTA]

This issue was actually rampant with the 2013 ATS (LTG engine). The reports were mainly on stock vehicles. It's happened to many 2013 Malibu's as well. According to GM engineers, there was a slight piston re-design (we don't know if this is actually true) in the later half of 2014 that corrected the issue. Also, the Malibu and ATS received recalls that updated the calibration and replaced the spark plugs last year. Even now, though, there are still reports of even the newer 2015 ATS's having failures.

My own personal 2014 Regal GS had the failure with only 2k miles on the odometer back in March of 2014. I hadn't installed a calibration on it yet since I was still enjoying and getting a feel for how she operated completely stock. Simply out of the blue one day she started running rough, like the OP mentioned in his very own description. The engine was replaced under warranty. I haven't had an issue, not one, since. So, I sort of lean towards believing that GM changed the piston design or performed some sort of minor update to the engine since it's been great ever since.

There could also, and more believably, have been a run of a batch of 'bad pistons' whos metallurgic makeup was flawed somehow which could explain why so many 2013 ATS and early 2014 LTG Regal's were affected.

 

[neverstock]

Hi I'm new to the forum and looking for help!

Leased a 2016 Regal GS at the beginning of this year and have been running it with an INJEN CAI for a couple months. I am planning to tune the car in the very near future, however, I'm starting to get symptoms including misfire on cold start up, rough idle when its hot and more recently loss of power and misfire under moderate acceleration, intermittent CEL and a couple times a message popped up saying something like 'automatic collision prep unavailable'.

Worried that these are symptoms of a cracked piston like so many 2013/14 ATS owners experienced. Car only as 4K miles on it. Any ideas before I put stock intake back on and bring to dealer? I hate dealers because they all to often make matters worse!

 

[stoopid]

Hi I'm new to the forum and looking for help!

Leased a 2016 Regal GS at the beginning of this year and have been running it with an INJEN CAI for a couple months. I am planning to tune the car in the very near future, however, I'm starting to get symptoms including misfire on cold start up, rough idle when its hot and more recently loss of power and misfire under moderate acceleration, intermittent CEL and a couple times a message popped up saying something like 'automatic collision prep unavailable'.

Worried that these are symptoms of a cracked piston like so many 2013/14 ATS owners experienced. Car only as 4K miles on it. Any ideas before I put stock intake back on and bring to dealer? I hate dealers because they all to often make matters worse!

Remove the CAI and see if the problems go away.

Fwiw, you need to tune the vehicle to gain anything other than noise from having the CAI. Additionally, most tunes would help prevent and/or clear the CELs.

 

[neverstock]

Yes, i realize it doesn't really add power in stock form but sounds cool and was just the beginning of upgrades. I'm going to put the sock intake back on this week end and decide next move. Should also mention my wife did fill it with 87 a couple times which makes me worried i did damage especially if the CAI makes it run leaner. First noticed the misfire after racing a VW GTI on a tank of crap 87 gas

 

[stoopid]

Yes, i realize it doesn't really add power in stock form but sounds cool and was just the beginning of upgrades. I'm going to put the sock intake back on this week end and decide next move. Should also mention my wife did fill it with 87 a couple times which makes me worried i did damage especially if the CAI makes it run leaner. First noticed the misfire after racing a VW GTI on a tank of crap 87 gas

I also forgot to mention that any air leaks in the installation of the CAI will also cause issues like you're experiencing.

 

[neverstock]

Update:

removed CAI and problem persisted. Misfire was not as noticeable with stock intake but still hesitated, misfiring intermittently under moderate acceleration.

Brought car to dealer this morning for oil change and to check out symptoms. They claim #3 spark plug was bad. Is it likely that crap gas fried one of the plugs?

Picked car up and haven't detected any misfire in first 15 miles of driving and feels like it pulls harder. Still idles rough when hot. I can live with rough idle as long as it's not a problem with the car. Is this normal for these engines?

 

[stoopid]

"Rough" is hard to quantify in words. Most cars idle, well, rough(er) than most car owners would like. Does it idle rougher in gear, vs being in neutral? Do you use the air conditioning a lot?

Glad it was only a plug. After a few more miles of testing, get that CAI back on there and get the tune applied. 😀

Have you tried any gas treatments?

 

[neverstock]

When it's cold it idles smooth IMO. Very slight vibration but with music on quietly you wouldn't know it's running.

When it's hot after 10 minutes of hard driving or on the highway it's a noticeable shake that you can feel even if music loud although i think it's somewhat less noticeable since the plug was changed.

used octane booster for a couple tanks... did you have something else to suggest?

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Seems equally rough in gear or in park (only when it's hot). Turning A/C on smooths it out a fair bit.

 

[stoopid]

When it's cold it idles smooth IMO. Very slight vibration but with music on quietly you wouldn't know it's running.

When it's hot after 10 minutes of hard driving or on the highway it's a noticeable shake that you can feel even if music loud although i think it's somewhat less noticeable since the plug was changed.

used octane booster for a couple tanks... did you have something else to suggest?

- - - Updated - - -

Seems equally rough in gear or in park (only when it's hot). Turning A/C on smooths it out a fair bit.

Might be a loose engine mount (?).

Techron and Gumout are good for ensuring the injectors are clean. Because these are DI engines you won't see much benefit using gas additives since gas isn't sprayed on the back of the valves (which is where the treatment/additive is most needed).

 

[neverstock]

More trouble!

1st Problem:
It took at least 5 seconds to start yesterday (pushed button sat back and listened to it cranking wondering if it would ever start before it finally caught). Drove it for a couple miles everything seemed fine. Parked for 20 minutes and restarted normally. Drove home without incident. Also been noticing rough idle is coming back again but not misfiring yet.

2nd problem:
Parked car in street on a hill with parking break on while i cut the grass. Drove around the block before pulling into my garage and noticed the transmission hesitated and shifted hard. pulled into drive way and found myself having to give it throttle to get into the garage when normally i'm idling with foot on the break to slowly roll into the garage. Almost seemed like parking break was stuck on but it wasn't slowing down any fast than normal. Only seems to have trouble accelerating. this morning my wife calls me to say that the engine is revving like crazy but going nowhere then jolts harshly and only going 5 mph max. She had to turn around and go back home and i'll be calling roadside to come pick it up.

Any ideas on what this might be i'd be glad to hear. Also if there's any connection between the 2 problems