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I have a 2019 LT, 1.5L and the power is hesitating really bad upon acceleration, but there are no codes triggering and the dealership keeps saying they can’t get it to happen for them... anybody else having similar problems.?
 

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2017 SS Sedan 6.2L
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There are a lot of things that can reduce power. If it's warm outside, the engine will succumb to heat soak and struggle if filled with regular 87 octane gas. If the air intake filter is clogged or the throttle body is really dirty it will also reduce power and acceleration from a stop. You didn't mention mileage, but if you are over 50-60,000 miles, you could need new spark plugs or have carbon build up on the ports and valves preventing airflow.
 

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2016 Malibu 1LT 1.5T/6-speed 6T40
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+1 on what @cp-the-nerd wrote. Many possibilities with so little info. When I see 2019 1.5T and reference to hesitation I immediately look to the problem linked below. It is a simple ECM update to fix a knock sensor anomaly. The dealer should at least make sure you are running the latest ECM calibration if they haven't already. This ECM update is the fix in most (but not all) of these scenarios.

The bulletin is in post two:
 
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It would be pretty sad if your dealership overlooked a service bulletin about your exact complaints, but it also wouldn't be surprising. If you go back to your dealership request that they check the TSB document in the thread linked above. (Bulletin 19-NA-058).
 

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Could it be related to the throttle position sensor issue on the Gen 9's? Spitballing, but I have on occasion noticed when the car is cold and I shift from reverse to drive after backing out of my driveway there is a slight hesitation in acceleration with even pressure applied to the gas pedal. I can most liken it to a bad battery connection where a light will flicker for a moment and then operate normally the rest of the time. Its not long enough to trip a MIL, but long enough for your body to sense the slight change in force.

Additionally I have found this condition when driving on flat road at a constant speed, with the car warmed up, with cruise control activated. I just assume that to be the CC software maintaining speed and it simply being in two different "cells" of the matrix at the same time. (anyone familiar with EFILive will understand the cell reference)
 

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It would be pretty sad if your dealership overlooked a service bulletin about your exact complaints, but it also wouldn't be surprising. If you go back to your dealership request that they check the TSB document in the thread linked above. (Bulletin 19-NA-058).
Would the car need the DTC set for them to investigate? That's the way the TSB reads, and would be an easy loophole for any dealer to use as a "problem could not be recreated" line we hear so often.
 

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2016 Malibu 1LT 1.5T/6-speed 6T40
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Re-check the knock sensor TSB I linked. It does not require a code set.
Some customers may comment that there is a hesitation / low power condition and/or MIL is illuminated with P2096 or P2097 set.
It may or may not be the cause, but it has been for a dozen 2019 owners and none had a code set or MIL on. Even more 2018ers but that is a different bulletin.

As for the pedal position sensor, it could always be the cause just like any drive by wire car but wouldn't be the issue specific to gen9. That issue requires MIL on with code P2138 set as it is a specific multi-sensor correlation issue. Plus, last I knew that was 2016-2018 and 2019s aren't included.
 
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Additionally I have found this condition when driving on flat road at a constant speed, with the car warmed up, with cruise control activated. I just assume that to be the CC software maintaining speed and it simply being in two different "cells" of the matrix at the same time. (anyone familiar with EFILive will understand the cell reference)
The TCM has a number of different shift logic patterns organized as separate data tables made up of "cells," so cruise control can indeed reference a different shift pattern than standard driving. However, I'm not sure what you are referring to as being in two data cells simultaneously. There can only be one shift pattern active at a time.
 

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2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
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... snip ...

Additionally I have found this condition when driving on flat road at a constant speed, with the car warmed up, with cruise control activated. I just assume that to be the CC software maintaining speed and it simply being in two different "cells" of the matrix at the same time. (anyone familiar with EFILive will understand the cell reference)
To the best of my understanding:

It will choose a single cell. If there are multiple cells vying for selection, the computer will have a method for identifying the best choice and make it.
 

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I have a 2019 LT, 1.5L and the power is hesitating really bad upon acceleration, but there are no codes triggering and the dealership keeps saying they can’t get it to happen for them... anybody else having similar problems.?
My ole lady has a 2017 doing some crazy stuff to it's the LT1 1.5 Liter 6 speed auto and not body can get a code and it's shifts hard acceleration is just haywire
 

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2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
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My ole lady has a 2017 doing some crazy stuff to it's the LT1 1.5 Liter 6 speed auto and not body can get a code and it's shifts hard acceleration is just haywire
Nobody can get a code? Odd. Is the CEL on and/or flashing?

How old is the battery? When was it load tested? How does the starter sound when the engine is being cranked?

How many miles? When was the last time the trans fluid was changed? What color is it now? Any odd smells, like being burnt or something else?
 
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