Air/fuel Ratio Meter.

[daktari]

Hi all.

i`m after a decent quality Air/Fuel Meter. Has anyone suggestions on the best place to buy one and what make etc? Not after one of those solder it together yourself jobs. Cant solder for toffee.

TIA :)

[djdna2000]

IMHO they are a waste of time. Unless you are talking about a wideband one. You won't be able to deduce anything useful from one you just attach to the standard narrowband sensor in the car.

edit: if you do want a wideband, then the LM1 is about US$300, very reasonable.

[daktari]

OKayyyyyyyyyyyyyy. Gonna show my ignorance now..... Wassa diffrence? Apart from the obvious. And about 100 quid.

I know the cheapy ones measure the ammount of oxygen via the lambda sensor. The wideband ones????

Bet they got more wires. :D

[ae111sr]

For lots of tech info take a look here

[daktari]

So i`m guessing that a wideband one would have to be wired into the ECU then?

[djdna2000]

Lambda sensors (oxygen sensors) fall broadly into 2 categories, wideband and narrowband.

Virtually all production cars are fitted with narrowband sensors. These aid the ECU in fuelling when in closed-loop mode, by giving it a rough idea of what the air/fuel ratios are. You can buy an air/fuel ratio meter to see what this is doing, but all you will really see is the engine running rich (which they are programmed to do) and not be gaining any useful information on how your car is running. It looks at a wide range of afr but yoiu really only care about the very small band around 14.7 which is the stoichiometric ratio. Very small changes here will completely affect the running of your car, but you will not be able to pick them up on a normal gauge from a narrowband sensor.

The wideband magnifies this area, and only has a range of a few points of afr. So you can really see what is happening to the ratio. However you cannot then do anything with this data unless you have a programmable ECU to alter stuff on (the Toyota ECU is locked down). So in answer to your question, no you do not connect it to the ECU.

[daktari]

Thats great. Done some reading up on the subject as well. :bookworm: It`s amazing what you can learn when you take the time,

Thanks for all your info. Very much appreciated.

:D