Hi all

I am trying to determine if there is a market for an idea I've been working on. Basically, it goes like this: replace the OEM oxygen sensor with a Wide Band Oxygen sensor and its necessary electronics, and also include a cockpit-mounted dial that allows you to set your A/F ratio at any point from ~10:1 to ~55:1.

I have already gotten lots of suggestions for additional features, like a 1 minute data log, a digital display of A/F, etc... but the system above is complete and works perfect, so I'm quite interested in hearing what anyone thinks about its usefullness.

This is not an Apexi type or VTEC controller, it doesn't lie to your MAP, so you really can acheive accurate A/F control.

In addition, this setup could be used as an A/F monitor, if it is not hooked up to the ECU it will merely read what the A/F is, and not control it. This is not how I intended it, but when I realized that it can be done for under $500 and I looked at the price of MoTeC's system, it becomes an interesting thought...

Please let me know what you think!!!

 

theres several other companies that offer similar units. directed engineering offers a wideband kit, and FJO also has a very nice one that untilizes data-logging.

neither of these units allow you to adjust your a/f though, they just display your a/f ratio via a wideband sensor that put in the bung supplied with the kits that you weld to your downpipe.

can you please explain a little more about simply putting a wideband in place of the stock o2, then have fuel control? does this still let the ecu make adjustment, or the user have full control over the a/f?. ive never heard of this kind of option unless you go stand alone.

 

How it works:

OEM oxygen sensor replaced by UEGO sensor. UEGO is wide-range; it can read A/F ratio from about 10:1 up to 50:1 or higher; OEM sensor only reads 'rich' or 'lean' of Stoic (14.7:1). All other wide-range sensors have a fairly flat output, so Vout of sensor is *roughly* linear with A/F ratio (temp and other things play into it, but the electronics take care of that...). This special controller changes that characteristic into a 'Z curve', just like the OEM sensor (output of OEM sensor is 1V for all ratios richer than 14.7:1, and 0V for all ratios leaner). The difference is that by adjusting the dial on the Cockpit Pod, this Z curve can be changed (shifted) to control at any air fuel ratio desired, as opposed to the stock sensor that always switches at Stoic. Thus, vehicles with mild to medium engine modifications benefit by being able to run a more suitable A/F ratio, usually on the rich side of Stoic. This is accomplished merely with the oxygen sensor, and all of the fuel injection parameters (transient operations, pulsewidth, timing, etc) can remain stock (or modified by some other ECU piggyback).

 

Sounds cool.

So basically your tricking the motor with the O2 sensor so that the ECU thinks the car is lean, so it richens it up?

 

The amount of fuel the ECU adds has to do with a lot more than the heated oxygen sensor. All you'll do is throw emissions control check engine lights.

 

How this will not work:
The output of a stock o2 sensor is 14.7:1=450 mV. Anything higher than that is rich anything less than that is lean. A UEGO wideband sensor has an output of up to 5 volts, So if your saying to send that signal to your factory ECU, then that is not going to work. Another thing is, your ECU only uses the input of your O2 sensor when it is in closed loop, when you are at wide open throttle, your ecu goes into open loop. A great idea, but if it was that easy, it would have already been done.

 

Still waiting for the reply AFguy.

You say but how does it work perfect?

When jdmcrx89 made some very good points.

 

Can be solved, but you will lose accuracy UNLESS you employ a great deal of circuitry.

Whether or not it will be more accurate than a stock O2 sensor... :dunno:

 

Even if you did spend the countless money and time on this project of converting the wideband signal into something your ECU can understand, the ECU still wont look at the O2 signal at WOT. So you might as well just buy a fuel controller and go to the dyno or Build the DIY wideband A/F meter .

 

Also the DIY wideband will work with HONDATA'S Rom Editor just like the Motec unit.