Chevrolet Malibu Forums banner

1 - 17 of 17 Posts

·
Registered
2018 Chevrolet Malibu Premier
Joined
·
5 Posts
Discussion Starter #1 (Edited)
I just picked up my 2018 Premier 2 liter turbo from the shop after a 2 week piston replacement at just 22000 miles. In early February I was accelerating from a stop and got to about 20 mph and my whole dash lit up and it died. I started it back up and it was chugging and smoking out the back. I got out and saw fluids under the car shut it off stepped away and had it towed. Dealer tore it apart and found 2 cracked pistons and replaced them all. In the meantime I searched online and found piston failure reports on Cruzes, regals, equinoxes, terrains, even corvettes. I removed chevy from the search and found fords and volkswagens doing it. When I picked it up the service guy had me meet with the tech that did the work and showed me the car. It was really clean and engine looked new no dust spotless. The tech told me some things that made no sense. He said I need to avoid premium gas which I had always been using. He said the problem is pumps that have a single pump and buttons to select grade. The last user might have used regular and even though I want premium a tiny amount of regular is still in the pump. It is a "one in a million" but if the car has heavily advanced timing and gets even a drop of that regular gas it cant compensate in time and fires before it should. So just use regular so the computer doesn't advance timing. He said I could also use pumps that have 3 different nozzles for each grade and should be fine.

I have a few questions for you all

1 why is this happening
2 is the gas pump thing even plausible and if not are these engines just pos junk
3 should i really use regular to avoid this
4 what exactly is advance timing and does it mean it uses more fuel and lower gas mileage if yes why not avoid that with regular anyway
 

·
Super Moderator
2017 SS Sedan 6.2L
Joined
·
5,020 Posts
First off, USE PREMIUM. The mechanic's logic about using regular is total nonsense.

Second, yes you will get a splash of regular gas in the tank when filling premium. Everything else your mechanic said about this is utterly wrong. Completely wrong. If you get 10 gallons of premium and half a gallon of regular, your engine will be FINE. It is not that sensitive to a splash of lesser gas.

Forget everything your mechanic told you about regular gas versus premium. Your engine failure happening in a 2018 model was an aberration.
 
  • Like
Reactions: SilverSport

·
Super Moderator
2016 Malibu 1LT 1.5T
Joined
·
2,675 Posts
I 2nd what @cp-the-nerd said; the mechanic telling you to use regular is bunk. You will have reduced power and likely reduced fuel economy.

From the manual:
For vehicles with the 2.0L L4 engine, premium unleaded gasoline meeting ASTM specification D4814 with a posted octane rating of 93 is highly recommended for best performance and fuel economy. Unleaded gasoline with an octane rated as low as 87 can be used. Using unleaded gasoline rated below 93 octane, however, will lead to reduced acceleration and fuel economy. If knocking occurs, use a gasoline rated at 93 octane as soon as possible, otherwise, the engine could be damaged.
There are only two other forum reports of the 2018 2.0T LTG suffering piston failure. All of the other cases are limited to 2016-2017 cars and one or two in gen8. While unpleasant, be thankful it at least occurred in warranty. Use 93 premium top tier fuel, stay up on those oil changes, and move forward.
 

·
Super Moderator
2017 SS Sedan 6.2L
Joined
·
5,020 Posts
One thing I want to clarify, when you fill up your gas tank with 93 premium and there's a splash of regular, the gas mixes together, so you have like 92.7 octane gas. The fuel injectors aren't getting random sprays of pure 87 octane. If that was a real problem, every premium-recommended engine in the country would be a timebomb with spark knock happening regularly.
 

·
Premium Member
Joined
·
1,655 Posts
Mechanic wants you to use regular so more piston jobs come into the shop. Job security at your expense.
 

·
Administrator
2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
Joined
·
18,196 Posts
@rightwingdan

I, too, will add my 2¢ to this discussion about that mechanic's faulty logic.

I usually fill up at the BP station nearby that has 87, 89, and 91. For a couple of weeks all they had was 87 octane. My 2011 Gen7 V6 runs better on 89, so that's what I wanted. They told me that they were out of 91, and since the pump mixes 91 and 87 to get 89, their 89 was also unavailable until they could get 91 again.

As @cp-the-nerd said, the fuel pumped into your tank might contain a bit of 87, but when you add in the 93, it mixes into a homologous octane of their averages, with 92.7 being a good likelihood.

The next time you talk to that mechanic, tell him to either stop in his tracks and support what he says, or just shut up. We've all done it, myself included: spoken when we thought we were right but we were dead wrong. He's dead wrong. Period.

I also believe that you should use only Premium fuel, and if you can find Chevron, see if that runs better than other brands. When we had it here in the local area, my car ran great.

Here's a little bit of reading you can finish in just a couple of minutes.
 

·
Registered
2018 Chevrolet Malibu Premier
Joined
·
5 Posts
Discussion Starter #8 (Edited by Moderator)
Thanks for the replies I'll stick with premium 93. I just dont understand why it broke in the first place i always use chevron or shell premium and it broke before. They gave me a 100,000 warranty on the replacement work so its good. I dont want ot trade the car in yet.

GM.......... what is with the stupid ass popups about a premium subscription? knock that stuff off I can barely type they keep popping up every 5 seconds after i close..
 

·
Registered
Joined
·
4 Posts
My 2018 2.0 just went in Friday and was diagnosed with piston failure. They also have to replace a catalytic converter they think is destroyed. It has 53000 miles and it is fully covered by powertrain warranty. I had been under the impression it was the 1.5 that had piston issues but when i googled chevy 2.0 piston failure I found hundreds of posts about piston failure in Camaros Buicks Cadillacs and a couple dozen 2.0 Malibus here. I am pretty good about oil changes around 6000 miles and always use unleaded 93. Does anyone have insight as to why this is happening?
 

·
Registered
Joined
·
801 Posts
all GDI engines suffer from LSPI. What kind of oil did you use? I'm also suspecting the stock tune isn't that good.
 

·
Registered
Joined
·
127 Posts
2l turbos MUST use premium gas. This has been an issue since 2013. I noted that my usage and maintenance costs escalated with my gen 8 Malibu due to the requirement of synthetic oil and premium gas. I must say, however, that the car returns outstanding service, performance and reliability even over my previous Malibu. So far I have had 41,000 miles on my Malibu and it remains in good health. I've read from some owners reaching over 100k miles on their turbo engines, so an extended life is certainly possible.
 
  • Like
Reactions: DrivenDaily

·
Registered
Joined
·
127 Posts
Another thing; I tend to be anal with oil changes and I change my oil between 3,000 and 4,000 miles. I don't mean to draw a discussion about the oil change interval but to only say that this rule has kept me from engine failure due to poor oil. Oil gets contaminated with extended use, and if you are running 6 or 7 thousand miles with little or no service to the oil then it can (will) cause engine wear issues.
 
  • Like
Reactions: DrivenDaily

·
Super Moderator
2016 Malibu 1LT 1.5T
Joined
·
2,675 Posts
2l turbos MUST use premium gas
Yes. Pretty unfortunate/disturbing a tech would tell an owner that always uses Premium to forgo that in favor of regular. Premium obviously didn't prevent these guys from blowing pistons but regular won't help improve chances. Good thing owners have these forums to help combat unwise advice.
 

·
Registered
Joined
·
4 Posts
all GDI engines suffer from LSPI. What kind of oil did you use? I'm also suspecting the stock tune isn't that good.
I used a mix of $50 dealer oil changes and when they are busy a local lube shop that does mobil1 for a ridiculous 69.95. I used to do them myself but after age 50 my back couldn't take it anymore. I want to keep the car so maybe I'll try and shorten the oil change interval to 4000-5000 miles as suggested.
 

·
Registered
2018 Chevrolet Malibu Premier
Joined
·
5 Posts
Discussion Starter #17
6 months later and my 2018 2.0T is doing just fine after piston replacement. The work seems fine. I'm still using all Premium fuel but as others have said I changed to having oil done at 5000 miles.
 
1 - 17 of 17 Posts
Top