Date   : Sun, 21 Nov 2010 11:57:54 -0600
From   : jules.richardson99@... (Jules Richardson)
Subject: Using a Beeb for engine monitoring

Alex Taylor wrote:
> On 21 November 2010 15:16, J.G.Harston <jgh@...> wrote:
> 
>> It does have an ECU, with various input and output signals that I
>> might be able to play with.
> 
> It's interesting that someone should mention this. I've got a couple
> of cars completely devoid of electronics - i.e. carburettors, manual
> chokes, points ignition and so on.

Yeah, my truck's like that - nice and easy to work on when something goes 
wrong. There's only two fuses for the entire system. Even the voltage 
regulation is electro-mechanical rather than solid-state.  About the only 
thing I miss is a rev counter.

 > I've often wondered if such things
> as universal fuel flow and speed sensors can be bought separately, in
> order to create a trip computer with a realtime MPG readout. 

I believe so, but I think modern ECUs calculate consumption using the normal 
engine sensors (crank speed, throttle position, airflow at the intake etc.) 
don't they? You could add those reasonably easily, but then you'd have to do a 
lot of interpretation of the data to work out the actual consumption.

Personally I've never seen the need for such a readout though - for any 
vehicle that you drive often, you get to know how it's likely to behave for 
different loads, speeds etc. and the type of driving that makes it most fuel 
efficient.

cheers

Jules