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Air fuel monitoring
76camper - March 31st, 2006 at 10:44 AM

Has anyone fitted a universal oxygen sensor to their vw and connected it to an air fuel ratio gauge to monitor the air fuel ratio. Was thinking this wouldnt be too expensive as oxygen sensors are only $30 and jaycar/dicksmiths probably have an air fuel ratio kit.

Is the o2 sensor mounted before or after the cat converter on modern cars? Seems to be the only possible downfall as air cooled vw's dont have cat converters...


EgeWorks - March 31st, 2006 at 06:30 PM

Hi, I have an o2 sensor in my bug connected to an air/fuel gauge. It is out of a VS or VN commodore or something. Works fine. I installed it just after the merge on my extractors. It was pretty easy to hook up.


76camper - March 31st, 2006 at 07:48 PM

yea, just gotta find a set up that will be accurate. Wonder if there are any kits which come with an o2 sensor and gauge.... what gauge are you using, have you checked for accuracy?


EgeWorks - April 2nd, 2006 at 08:01 AM

I'm using a very pretty Autometer gauge (retails around $140). As far as I can tell mine is accurate, just have to wait till the engine/exhaust warms up, but that's to do with the sender not the gauge. I think most kits have about 6-8 LEDs which show lean-good-rich. My one has proabably 20-30 steps. I don't think that the kits come with a sensor but mine was $5 from pick-a-part.

I've used it to tune out a couple of lean spots, and since I can't easily find the time to take my car to a dyno it was worth the expense.


76camper - April 2nd, 2006 at 10:33 AM

I was thinking about something like this

http://www.jaycar.com.au/productView.asp?ID=KC5300&CATID=&keywords=&SPECIAL=&...

Have you hooked your car upto an exhaust analyzer and compared the reading to your gauge?

cheers


reub - April 2nd, 2006 at 10:47 AM

This is what I'm running in my bug http://plxdevices.com/

...the M-300 series http://plxdevices.com/products_M-Series-Controllers.htm

The thing you'll find with the autometer and jaycar afr meters is they're not wide band to give an accurate real time indication for what is going on with the cars afr - which is really required to help with a decent tune.

Here is a link to a little more 'tech talk' on the subject http://www.forparts.com/BoswidebandO2.htm

Hope this helps :thumb


76camper - April 2nd, 2006 at 03:49 PM

so how accurate will the jaycar kit be?

How much will the m-200 kit cost? Where might i find one?

cheers, they look the goods

[ Edited on 2-4-2006 by 76camper ]


reub - April 2nd, 2006 at 10:41 PM

I think it is a case of you get what you pay for to be honest. Th Jaycar kit may work but will not respond or display per the article previously posted.

With regards to the plx devices you have to purcahse them direct from America - unsure if there is an Australian distributor. There are a number of wide band afr meters on the market, you'll just have to research them.

There is also a realisation to what you expect from an afr. For me I'm at the high end of performance with my installation and need to know real time the current afr, your requirement may be different....

again, hope this helps. I'm by no means a guru on any of this tech stuff. Just know what I'm told from reading and reliable sources, like my mate Ian in Cairns...