Jaycar DIY Air/Fuel Ratio Meter kit

[3/4/2001] Reviewed by: Matt King - matthew.king@osi.varianinc.com

A kit for constructing your own air-fuel ratio meter. The kit comes with all necessary components, PCB, a generous length of wiring, a short piece of solder and a detailed and informative instruction sheet. All you need is a soldering iron, a minimum amount of soldering ability, and about 30 minutes tops. The kit is available online at www.jaycar.com.au and they can ship overseas. The kit part number is: KC-5195.

The kit is very easy to assemble and install. The meter connects to power (ignition switched), earth - I suggest the engine block, and of course the oxygen sensor output. The kit does not come with a case or box, but this allows you to customize the fitment to any car (for example, if you wanted the LEDs in a circle to fit into an air vent). I had a problem burning out the IC due to voltage spikes, but a few simple components (two resistors and a diode) can be added to the circuit to prevent this happening. I also replaced the 10 separate LEDs with a 10-LED bar graph display (part number ZD-1702 from Jaycar) that lines up exactly with the PCB. This meant I could tuck the PCB under the steering column trim panel, leaving only a 5mm high bar display visible just below the dash. Photos of my installation can be viewed here: http://albums.photopoint.com/j/AlbumIndex?u=849260&a=11152929&f=0

For about US$15, you can make yourself this mixture meter that works just as well as the expensive aftermarket items and can be mounted more discretely. In other words, perfect for home tuning, or ensuring your turbo car does not run lean. Note that all O2-sensor based mixture gauges are only as accurate as the oxygen sensor output, and hence they are not really suitable for precise mixture tuning.

Under 30 minutes to remove completely

Back to Product Reviews 15 December, 2001