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2015 Chevrolet Malibu LT 1LT, 2.5L DOHC Ecotec, 6-speed Auto
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Oh, and I almost forgot, these engines are designed to run Premium fuel, which means you need to be over 91 octane fuel. And it need to be a Top Tier fuel. It can't be John Q. Public's Quick Stop fuel, because they are $.04/gallon cheaper than your local Top Tier brands.

Top Tier is not allowed to be advertised, unless the fuel is tested by GM and meets GM's standard level of additives needed to keep the fuel pump sock and the injectors clean. GM has a standard, the requires a higher % of detergent and additives, than what the U.S. EPA requires in the fuel. Adding the additives increases the production costs of gasoline, which is why Top Tier fuel is typically a little higher costs, than the EPA mandated fuel at Quick Stop. If your sock or your injectors become contaminated, you WILL develop a LEAN air fuel ratio, and that is BAD for any engine, ESPECIALLY a BOOSTED engine. If a lean condition is left, unchecked, for too long it WILL eventually lead to a melted/cracked piston OR a burnt valve. Both of those cause the cylinder to be "low", which refers to the compression in psi. I don't know the technical specs of of your engine. NA engines are usually around 200-220psi at optimum compression levels. Their service limit is usually between 180-190psi. If compression is lower than the service limit, the engine needs to be rebuilt or replaced. Lean conditions increase combustion temperatures and increase your NOx emission, which out undue stress in your EGR system(if equipped).

Running 89 or 87, will save you now, but will cost you much more later, in lost fuel economy, lost performance, as the knock sensor will detect detonation and retard ignition timing. This will increase emissions, as the fuel is not properly burning in the cylinder. The turbo may even be programmed to reduce your boost pressure, to prevent destroying the engine under WOT conditions. My dad's 1988 Turbo Thunderbird was setup that way, so I would imagine since turbo engine physics and thermodynamics have not changed in 40 years(or ever for that matter), that the tuning for the turbo and engine control modules have not changed much either.

On 87 or 89, when you are under load, at lower RPMs(such as towing or going up a steep hill), you will hear the spark knock, as a faint pinging sound. This is bad, and since combustions temperature so high the fuel begins burning before the spark has fired, you get vibration (damaging harmonics), and you can damage the pistons and valves.

Do you see the pattern, here?

Use oil the GM has not approved in your car and/or go too long before changing your oil - Blow a piston(why an petroleum producer would out calcium in oil is beyond me, because calcium is both very volatile and extremely abrasive)

Use incorrect octane fuel - Blow a piston or a valve (usually the exhaust valves because they get hotter and more carbon buildup than the intake valves do)

Use a non-Top Tier fuel - Blow a piston or a valve.

Trust me, spend the few extra bucks on the right fuel and oil for you car. You will enjoy your Chevy experience so much more, and come to respect GM for their innovation and legendary reliability. It will save you so much more money and headaches over the life of your vehicle.
 

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2016 Malibu 1LT 1.5T/6-speed 6T40
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As an add-on, in 2017 GM moved the 2.0T fuel octane rating from 91 or higher to 93 "highly recommended" (page 268 user manual). The manual says fuel as low as 87 can be used but "if knocking occurs, use a gasoline rated at 93 octane as soon as possible, otherwise, the engine could be damaged". Apparently GM isn't too confident their ignition timing compensations are bullet proof. Use the "highly recommended" 93 in the Top Tier flavor.
 
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2015 Chevrolet Malibu LT 1LT, 2.5L DOHC Ecotec, 6-speed Auto
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Absolutely, on that note. The PCM can only retard the advance curve for so much, before misfires occur and the O2 sensor will be out of its operating range for then short term/long-term fuel trims

My Owner's Manual states the 2.5L Engine can safely run on 87, without any issue, but that engine has a static compression ratio of 11.3:1. Once you hit 10.5:1, on an NA engine, you should be running premium fuel.

So, I use ethanol-free premium, which is both a Too Tier fuel (Citgo brand fuel)& 90 octane. I don't know if the PCM will add enough additional advance timing to take full advantage of the higher octane or not, like turbo engines will, but I average 33.5mpg, combined city highway, and the car is rated at 29/36, respectively.

Man, you definitely know you stuff. If I into a problem, I am gonna make sure to get in here and see what we can come up with.

US News, which is an independent, third-party tester if various used cars, rates the 2015 Malibu LT with a rating of 8.6/10 for reliability, so I may proud of my newest Chevy purchase
 

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Something to thing about? When you start out at lights getting on the freeway, or Passing someone. Does your ears love the sound of the engine. Then does your brain tell your foot to lay down. To have that sound and feeling. Well if so those pistons are not made like your grandpa’s in his old cars. To get the mileage they get today. They have lighten up the vehicles every where. Including engines. Now I can’t tell you not to do it, but your mechanic will be your best friend as long as the cash or credit card. Keep pumping out the funds for repair or replacement. If this is your problem think about putting in a race engine that is built to Hall your back side down the road.for a price $$$$$$.00.
 

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Oh, and I almost forgot, these engines are designed to run Premium fuel, which means you need to be over 91 octane fuel. And it need to be a Top Tier fuel. It can't be John Q. Public's Quick Stop fuel, because they are $.04/gallon cheaper than your local Top Tier brands.

Top Tier is not allowed to be advertised, unless the fuel is tested by GM and meets GM's standard level of additives needed to keep the fuel pump sock and the injectors clean. GM has a standard, the requires a higher % of detergent and additives, than what the U.S. EPA requires in the fuel. Adding the additives increases the production costs of gasoline, which is why Top Tier fuel is typically a little higher costs, than the EPA mandated fuel at Quick Stop. If your sock or your injectors become contaminated, you WILL develop a LEAN air fuel ratio, and that is BAD for any engine, ESPECIALLY a BOOSTED engine. If a lean condition is left, unchecked, for too long it WILL eventually lead to a melted/cracked piston OR a burnt valve. Both of those cause the cylinder to be "low", which refers to the compression in psi. I don't know the technical specs of of your engine. NA engines are usually around 200-220psi at optimum compression levels. Their service limit is usually between 180-190psi. If compression is lower than the service limit, the engine needs to be rebuilt or replaced. Lean conditions increase combustion temperatures and increase your NOx emission, which out undue stress in your EGR system(if equipped).

Running 89 or 87, will save you now, but will cost you much more later, in lost fuel economy, lost performance, as the knock sensor will detect detonation and retard ignition timing. This will increase emissions, as the fuel is not properly burning in the cylinder. The turbo may even be programmed to reduce your boost pressure, to prevent destroying the engine under WOT conditions. My dad's 1988 Turbo Thunderbird was setup that way, so I would imagine since turbo engine physics and thermodynamics have not changed in 40 years(or ever for that matter), that the tuning for the turbo and engine control modules have not changed much either.

On 87 or 89, when you are under load, at lower RPMs(such as towing or going up a steep hill), you will hear the spark knock, as a faint pinging sound. This is bad, and since combustions temperature so high the fuel begins burning before the spark has fired, you get vibration (damaging harmonics), and you can damage the pistons and valves.

Do you see the pattern, here?

Use oil the GM has not approved in your car and/or go too long before changing your oil - Blow a piston(why an petroleum producer would out calcium in oil is beyond me, because calcium is both very volatile and extremely abrasive)

Use incorrect octane fuel - Blow a piston or a valve (usually the exhaust valves because they get hotter and more carbon buildup than the intake valves do)

Use a non-Top Tier fuel - Blow a piston or a valve.

Trust me, spend the few extra bucks on the right fuel and oil for you car. You will enjoy your Chevy experience so much more, and come to respect GM for their innovation and legendary reliability. It will save you so much more money and headaches over the life of your vehicle.
I'll second you top tier fuel recommendation, though I am not a fan on over changing the oil, as they is little need to. The manufacturers do a bit of research to justify their recommendations. Be realistic in following their schedule and you should be fine. I believe its better for the average joe to spend the extra $$$ (they would have spend on too frequent oil changes) on top tier gasoline, since it should keep the engine cleaner (to avoid PI).

Calcium in its bound form, is necessary in oil (or magnesium or other acid reducer). It corrects the acid produced by the combustion process.
 

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Discussion Starter · #26 ·
yes it’s a recall problem Chevy will fix it for you it hasn’t happened to mine yet but I know of a lot of ppl going through this
I asked about this and was told there is no recall on any of the engines.
 

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Discussion Starter · #27 ·
I want to say a big THANK YOU to campb292. He exchanged some messages with me and helped me get this resolved in a fair way. Got a new engine with a 3 year 100,000 mile warranty and didn't bleed out on the floor paying for it. Should never happen on a car with 71,000 miles. After conversations with the manager I want to recommend everyone get their oil changed at 33% on the oil life monitor which is usually 5000 miles. Manager says the interval is just way to long on these. Please close this conversation down as resolved.
 

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2016 Malibu 1LT 1.5T/6-speed 6T40
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I am glad it worked out.

What the manager said is very good advice. I like to change oil and filter between 5000-5500 miles. Some that drive less should be changing every six months if they don't reach 5000. Oil condition isn't just about lubrication and wear anymore. That's old obsolete thinking. Oil picks up contaminants and that ends up on intake valves and in the PCV system. Sludge, even if it is being cleaned by new oil, eventually makes it's way to the intake valves and clogs up the PCV system. The engineers made solid choices to get a car to 60,000-100,000 miles during which GM has warranty liability. If you want less maintenance and less risk beyond that, change the darn oil. And yes always use Premium 93 Octane Top Tier fuel in the 2.0T LTG.

Good luck with your car. Discussion closed per OP request.
 
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