The invention is directed to a method for reducing low speed pre-ignition events in a spark-ignited direct injection internal combustion engine by supplying to the sump a lubricant composition which contains an oil of lubricating viscosity and an ashless dispersant. The ashless dispersant may be selected from succinimide compounds prepared from aliphatic or aromatic amines.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition includes a major amount of a base oil, one or more overbased calcium-containing detergents having a total base number of greater than 225 mg KOH/gram, to provide greater than 900 ppm by weight to less than 2400 ppm by weight of calcium to the lubricating oil composition, and a low speed pre-ignition reducing amount of one or more titanium-containing compounds to provide from 10 ppm to 3000 ppm titanium and/or one or more tungsten-containing compounds to provide from 125 ppm to 3000 ppm tungsten, all based on the total weight of the lubricating composition. The low speed pre-ignition events in the boosted internal combustion engine may be reduced relative to a number of low speed pre-ignition events in the same engine lubricated with the same lubricating oil without the titanium- and/or tungsten-containing additive.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition includes greater than 50 wt. % of a base oil, an overbased detergent having a TBN greater than 225 mg KOH/g and a low-based/neutral detergent having a TBN up to 175 mg KOH/g. A total amount of calcium from the overbased and low-based/neutral detergent is greater than 1100 ppm to less than 2400 ppm by weight based on a total weight of the lubricating oil composition. The lubricating oil composition and method may be effective to reduce low-speed pre-ignition events in a boosted internal combustion engine lubricated with the lubricating oil composition relative to commercially available lubricating oil compositions.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition has not more than 150 ppm sodium and includes a major amount of a base oil and an additive composition that includes one or more overbased calcium-containing detergents having a total base number of greater than 225 mg KOH/gram, in an amount sufficient to provide greater than 1100 ppm by weight to less than 2400 ppm by weight of calcium to the lubricating oil composition, and one or more molybdenum-containing compounds in an amount sufficient to provide at least about 80 ppm by weight molybdenum to the lubricating oil composition, all based on the total weight of the lubricating composition. The oil and method may reduce low-speed pre-ignition events in the boosted internal combustion engine relative to a number of low-speed pre-ignition events in the same engine lubricated with a reference lubricating oil.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition includes greater than 50 wt. % of a base oil, one or more overbased calcium-containing detergents having a TBN greater than 225 mg KOH/g and one or more magnesium-containing detergents. A total amount of calcium from the one or more overbased calcium-containing detergents is from 900 ppm to less than 2400 ppm by weight, and a total amount of magnesium from the one or more magnesium-containing detergents is from 50 ppm to 500 ppm by weight, both based on a total weight of the lubricating oil composition. The lubricating oil composition and the method of using it are effective to reduce low speed pre-ignition events in a boosted internal combustion engine lubricated with the lubricating oil composition.

A lubricating oil composition and method of for providing an acceptable number of low-speed pre-ignition events in a boosted internal combustion engine using the lubricating oil composition. The lubricating oil composition includes greater than 50 wt. % of a base oil of lubricating viscosity, and an additive composition that includes an overbased calcium-containing detergent having a TBN greater than 225 mg KOH/g, and one or more zinc dialkyl dithiophosphate compounds are derived from a molar ratio of secondary alcohol to primary alcohol of 20:100 to about 100:0 and have an average total carbon content of greater than 10 carbon atoms per mole of phosphorous. The lubricating oil compositions contains the overbased calcium-containing detergent in an amount to provide greater than 900 ppm to less than 2400 ppm by weight calcium, and at least 0.01 wt. % of the zinc dialkyl dithiophosphate, both amounts based on the total weight of the lubricating oil composition.

A lubricating oil composition and method of operating a spark ignition combustion engine. The lubricating oil composition includes a major amount of a base oil of lubricating viscosity and an additive composition that includes an over-based detergent and a low-based/neutral detergent, wherein a total amount of calcium from the over-based and low-based/neutral detergent ranges from greater than 1100 ppm by weight to less than 2400 ppm by weight based on a total weight of the lubricating oil composition. The lubricating oil composition is effective to reduce low-speed pre-ignition events in a turbocharged gasoline engine lubricated with the lubricating oil composition.

A method of communicating by a Radio Frequency Identification (RFID) reader includes transmitting, by the RFID reader, a continuous radio frequency (RF) wave at a first frequency. The method also includes adjusting, by the RFID reader, the first frequency of the continuous RF wave to a second frequency and then receiving a backscattered RF wave at the first frequency from an RFID tag. The backscattered RF wave is generated by the RFID tag in response to the continuous RF wave of the first frequency. A difference between the first frequency and the second frequency is equal to or greater than a frequency difference threshold to reduce interference between the backscattered RF wave and the continuous RF wave.

A method for preventing or reducing engine knock or pre-ignition in a high compression spark ignition engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition that contains (i) a lubricating oil base stock comprising at least one branched ester having at least about 15% of the total carbons in the form of methyl groups, and (ii) at least one ashless antiwear additive selected from a phosphorus-containing ashless antiwear additive, a sulfur-containing ashless antiwear additive, and a phosphorus/sulfur-containing ashless antiwear additive. A lubricating engine oil having a composition that contains (i) a lubricating oil base stock comprising at least one branched ester having at least about 15% of the total carbons in the form of methyl groups, and (ii) at least one ashless antiwear additive selected from a phosphorus-containing ashless antiwear additive, a sulfur-containing ashless antiwear additive, and a phosphorus/sulfur-containing ashless antiwear additive. The lubricating oils of this disclosure are useful as passenger vehicle engine oil (PVEO) products.

A method for preventing or reducing engine knock or pre-ignition in a high compression spark ignition engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition that contains (i) a lubricating oil base stock comprising at least one ester including at least one group selected from the group consisting of Formula (1), Formula (2), and Formula (3):

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The lubricating oils of this disclosure are useful as passenger vehicle engine oil (PVEO) products.