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2016 Malibu 1LT 1.5T/6-speed 6T40
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These cars are direct injection. Nothing you add to the fuel will clean the intake valves. Top Tier Fuel, dexos1 oil (gen2/3), and the oil separator are how you prevent/slow buildup from forming in the first place. The service the dealer does is a chemical cleaning of the intake system. Chemical isn't as good as manual/mechanical but easier. Did they scope the intake ports? Some ugly stuff would have to be happening to catastrophically restrict the intake ports at just 78k. There are dozens of gen9 1.5/2.0 owners on this forum over 100k without intake carbon symptoms. I'm not sold on that as the cause here knowing the throttle body wasn't that dirty. The dealer has seen the car though, let them do their thing. Hopefully it works but be prepared for more work.
 

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2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
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Here is a great video to learn a bit about DI engines.

 

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2016 Malibu 1LT 1.5T/6-speed 6T40
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Here is a great video to learn a bit about DI engines.

Good video for basics of direct injection but predictions are funky. With savage goose guy's 30,000-60,000 mile "endgame" prediction I wonder how he reconciles direct injection cars going well beyond that with none of the carbon maintenance? This forum is full of 2.5, 2.0, even starting to see some 1.5 getting 100k-200k+ on the odometer.
 

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2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
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Its value is in seeing the result of build-up on the intake valves, which, as stated above, can't be cleaned by the use of any chemical added to the fuel.
 

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Did anyone check their car for a vacuum leak at the intake? That would cause a power loss issue and it’s not uncommon as you get up in mileage. my 2016 Chevy Malibu has 212000 miles on it and I just had my RPM gauge revving from 800 to 2100 up and down several times while I was sitting in park in a parking lot. Some of the issues in this thread sounds like some of you might need to clean your fuel injectors which if they’re plugged it will cause it to stall. I am thinking my car needs an idle air control valve or has a vacuum leak somewhere. Any thoughts?
 

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2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
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Did anyone check their car for a vacuum leak at the intake? That would cause a power loss issue and it’s not uncommon as you get up in mileage. my 2016 Chevy Malibu has 212000 miles on it and I just had my RPM gauge revving from 800 to 2100 up and down several times while I was sitting in park in a parking lot. Some of the issues in this thread sounds like some of you might need to clean your fuel injectors which if they’re plugged it will cause it to stall. I am thinking my car needs an idle air control valve or has a vacuum leak somewhere. Any thoughts?
Your car does not have an IAC valve. It is DBW (drive by wire), so the TB (throttle body) is fully controlled by the computer. When it wants more air in the intake, such as during a cold start or operation of the AC, it will open the throttle further. No more need for an IAC system at all!

If the fuel injectors are dirty, then the fuel could be changed to a brand that is listed as a Top Tier Fuel, and/or adding Techron or some other cleaner that has a history of working well.

The RPM gauge is called a tach, or tachometer. Your tach bouncing up and down from 800 to 2100 and back suggests that your foot was on the gas pedal or there is a serious issue that would also illuminate the CEL/MIL. At that point, you'd want to scan it for DTCs (diagnostic trouble codes) and then figure out what's going on.
 

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My foot wasn’t on the pedal at all and the gauge was jumping. There are no stored CEL/MIL lights stored or pending in my GM service scan tool software.
Took a can of carb cleaner and found the vacuum leak at the air intake which didn’t take long to find.
 
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