I've been having issues with my N16 Euro Spec Pulsar with QG18DE engine going through 20 litres of fuel in 165 km. Had a cam angle sensor fault code we reset. Had a couple of dodgy coils, replaced them. Then no reading from 2nd O2 sensor, replaced that. Replaced MAF sensor. Got close to 200 km from 20 litres. I was playing around the other day unplugging coils one at a time and thought I would unplug cam angle sensor while the car was running. Well now I have check engine light on and the bloody thing runs sweet and uses bugger all gas now. I guess the timing chain is stretched. But problem fixed for now in my opinion.