| abstract |
The present invention relates to lubricating oil compositions, methods of reducing low speed pre-ignition (LSPI) in direct injection spark-ignition internal combustion engines, and the use of lubricant compositions to reduce LSPI events in such engines. Preferably, the composition comprises a detergent package comprising a calcium borate detergent, wherein the detergent package provides the composition with a calcium content of at least 0.12 wt%, based on the weight of the composition, and wherein the calcium borate detergent provides the composition with a boron content of at least 100ppmw, based on the weight of the composition. Optionally, the composition comprises a first detergent comprising a calcium detergent and a second detergent comprising a calcium borate detergent. |