http://www.pelicanparts.com/techarticles/mult_air_fuel_monitor/mult_air_fuel_monitor.htm
looks fairly simple any electronics people want to comment ?
the more you look:
http://www.scirocco.org/tech/misc/afgauge/af.html
[Edited on 17/1/06 by givemethebighammer]
I agree that looks pretty easy to wire up, and the parts should be easy to get.
Not sure I'd want to use an interference fit for the sensor. welding a tapped boss on the manifold sounds like a much better idea to me.
Real question is it useful or just another guage that isn't doing much except adding weight. If self mapping a megasquirt it's probably a
good idea, if having it set up on a rolling road less so.
Had one in my car for a couple of years, costs pence to make 10 leds an IC and a couple of resistors if I remember correctly.
Bought a lamda sensor of ebay for about £30 ,and welded the correct nut on the manifold.
It has been very useful for DIY carb jetting, at least you can get the mixture somewhere near sensible.
It's a bit dodgy looking at the gauge to check the top end jetting on the motorway at ***mph!!!!!
Just built one of these for a guy at work who races an MG, got the lambda sensor of ebay for £15, the rest of the bits would cost less than a
tenner.
works well on the bench,will let you know how it goes in his car.
Ray
I think I'll have a go at one, looks like it would be useful for tuning the carbs. What sort of lambda sensor would I need, loads on ebay at the moment - too many to choose from !
Only real problem with that setup is that it's designed for a narrowband sensor...therefore not in the same league as the wideband ones discussed
here
Key difference between wideband and narrowband is that the narrowband only has a relatively small operating range that is of any use - anything
outside this range is equivalent to a simple "too rich/lean"
Good talking point on the dashboard, though - and probably pretty useful once you're in the right ballpark...
we got a 4 wire sensor(built in heater).
try and get the boss with it if you can, we didn't and should have really
will try and get some pics of the one i built, if you like
Ray
Can you not use a wideband sensor and a digital volt meter?
Do the wideband sensors need a controller?
quote:
Originally posted by Surrey Dave
Can you not use a wideband sensor and a digital volt meter?
quote:
Do the wideband sensors need a controller?
Wide band sensors aren't that simple to use, narrow band sensor are much simpler. I built a lambda tester about 7 years back when there was a
lack of test gear for lambda sensors around , the circuit was out on Dave Pallants Rover 800 website I recently discovered it is still aroundat a
different address
http://www.gaima.co.uk/www.pallant.f2s.com/rover/tech/lambda.htm#High%20Impedance,%20Fast%20Voltmeter%20for%20Testing%20Lambda
I would caution that this type of circuit is very sensitive and picks-up too much noise. I still have a couple of protypes around but don't use
them these days.
For a dash display these days I think I would jjust use an op-amp to drive a LCD volt meter module. Also a 4 wire heated lambda sensor will give more
reliable results than the cheaper ones with fewer wires.
The Innovate LC1 wideband O2 sensor and controller is a doddle to use.
It has 2 configurable analogue outputs, one could be used to drive a volmeter to give a linear AFR v Volts.
I paid just over 1/2 a locost unit (remember them) from Bill Shurvinton (UK).
See here for info
No connection.
Colin