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My 2018 Premier is currently having piston replacement done at the dealer. It is scheduled to be done by Thursday. In the meantime, I am researching more about LSPI (low speed pre-ignition) and SPI (stochastic pre-ignition) which seem to be interchangeable terms. I've read a lot about it here and at other online sources but one thing I can't figure out: Everything says if LSPI occurs it happens in low speed high-load operation. What is low speed high load operation? Nothing ever seems to detail what that means. Does low speed = low engine rpm and high load = complicated demand on the engine such as into a wind, uphill, passenger and/cargo weight?
 

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2011 Malibu LTZ 3.6L V6 Red Jewel Tintcoat
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Low speed = Low RPMS. High load = need for power to move the vehicle, whether a little or a lot.

Many turbo engines that last a long time tend to run boost only at higher RPMs, adding boost to a substantially more powerful engine to start with. These newer engines are made smaller for efficiency but are stuffed full of pressure at lower RPMs.

At lower engine speeds, when the driver calls on the engine to accelerate, it does so by receiving fuel and air, but it's pressurized air, not ambient. This is the time when LSPI rears its ugly head.

My guess is that if you were to accelerate aggressively and then cut back once you were closer to your desired speed, it would be better than accelerating modestly. However, that would add wear to other components. The most immediate and obvious result is it would reduce your mileage, the primary reason that smaller turbo engines were chosen to start with.

Catch 22.
 

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Around town, I keep the car's shifter in manual mode and keep the engine RPMs at 2000 minimum.
 
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