>Fill the tank, zero the counter, drive for a while (the longer the >better) refill the tank, and enter the fuel quantity used to refill. >During this process, we've been counting injector pulses, so we now >know that there are X pulses per gallon. (liter or whatever) How does that work, when the injector pulse widths vary with engine load etc. Tony PicNPoke Multimedia 16F84 Beginners PIC Tools. **PLUS** - PicNPlay - PicNPlan - PicNPrep - PicNPost PicNPort - DT Type Saver - *new* PicNQuiz. Recent addition - Hex To Source converter. http://www.picnpoke.com Email picnpoke@cdi.com.au