We have this Nissan Sentra 2.5 Spec V in the shop that is going through 4 litres of oil in 3200 KM. The 4 gas readings are 18 PPM HC, and O%CO at idle with 0 HC & 0%co at 2200 RPM. Compression is 185(all 4 cold) and 190-200( all 4 hot. No visible signs of leak... Login to read more.