Date: Wed, 02 Feb 2005 04:52:53 +0000 From: Pooh Bear <rabbitsfriendsandrelationsnospamail.com> Subject: Re: How does the CPU figure out how much gas?
Martin Rich wrote: > On Mon, 31 Jan 2005 17:14:31 +0000, Colin Stamp <colinnospamp.plus.com> > wrote: > > >It uses the same sender as the fuel gauge to find out how full the > >tank is. The MPG calculation only needs the ECU/speedo data and is > >quite accurate, but the DTE calculation needs the fuel sender info as > >well. Because of that, it isn't nearly so accurate - mine often reads > >more when I start up after parking on a hill than when I parked. Very > >handy as a rough guide though. > > > > I'd noticed this effect - sometimes quite dramatically when the tank > is close to empty, since in practice I use the DTE indication to see > how low I really am once the 'low fuel' light comes on. I've also > noticed the DTE increasing while on the move, particularly if you > accelerate away from a stop and then cruise for a while. Indeed - any such system has to take into account current consumption as well as average. Therefore it can only ever be an estimate until the tank's nearly empty at which point you'll notice the low fuel indicator anyway. Graham
 |
 |
 |
 |
 |
