I have an Apex-i auto timer that does A/F ratio read out. If I bought a wideband O2 sensor like the one that came on the lean burning civics of 92-95 (VX I think), would I get an accurate wideband readout? I don't see why this wouldn't work if I supplied the O2 sensor with the proper power and gnd. I have the timer currently hooked up to my factory O2 sensor, but of course it is not as accurate as a wideband would be. Does anyone have any input on this or seen it done?




[Modified by supercompact, 10:42 PM 1/21/2003]


[Modified by supercompact, 10:43 PM 1/21/2003]

 

what was the part number for the o2 sensor??

 

Im also intrested in the part number.

 

the apexi autotimer only reads from 0 - 1 volt. A wide band is normally 0-5 volts.

 

The following are part numbers for the sensor. The Echlin is the cheapest I've found at $139.

Honda 36531-P07-003
Echlin ECHOS791
Bosch 13246

 

In the picture it shows a reading of 2.35 volts. When the A/F light and O2 light are on, like in the picture, that is a representation of O2 sensor voltage. Are you sure that the apexi meter only reads up to 1 volt? That pic is a little misleading.

 

i don't think it will work, you'd need a proper module to read wideband sensor, i guess its possible to re-use the diplay, but won't be plug-n-play

 

I could of sworn it was only up to 0-1 volts...I'll take a look at my brother's wrx when I get a chance.

But your idea still won't work. A wideband o2 sensor needs a controller because it needs to be temp. controlled. By the time you get the wideband controller (techedge or fjo) you'll pretty much have spent close to 300 bucks to make something that is only $100 work. Plus if you spend like $300-$350...you can get the techedge with the sensor AND the display unit.

If I remember right, narrow band sensors are only 2 or 3 wires and widebands are 5 wires. One of those wires actually heat it up, thats where the controller comes into play. So your o2 sensor wouldn't evenwork..and if it did it wouldn't be accurate. Spring for the techedge and it'll even allow you to log to a computer..

 

Your probably right, mine fluctuates between 0.01 and 0.98 on my car, so maybe the picture on apexi's website is not accurate. Thanks for the info.

 

Yes, the Apexi timer only reads from 0-1 volts.

 

No, the Apexi Turbo Timer Reads more than 1V. It simply wires into the O2 voltage reading, so whatever voltage it puts out is what you see. Mine starts off close to 5V (4.9ish) after just starting the car, but after the O2 warms up it drops down between 0-1V. Not too sure how the techedge works, but I think you could read voltages. How accurately it displays A/F is a different story.....

 

damn..this is interesting. if this works, i can just wire the extra auto timer i have on my crx so i don't have to spend 300 on the techedge

Jeff-

 

Interesting...let us know how it goes...wanna get rid of the pinball machine!!

 

It can display voltage as high as it wants but it can't read the A/F ratio of up to 5 volts. It only "reads" the A/F for 0-1 volt.

 

actually, narrow band have heated and nonheated. the non heated is has 1 wire, and the heated have 4 wires. all wide band are heated. so if your car has heated o2 sensor, you could probably wire the wide band up to your stock o2 wires as heat control. the civic vx has a wide band which is 5 wires.

i have both the techedge and the apex timer. the apex timer has a votage table that can be alter the change the a/f reading. if the timer can read what ever voltage the o2 puts out, you can change the table to get the correct a/f reading. or just use a volt meter to read a/f

 

My stock O2 is a heated narrow band (4 wire). If I wire the VX wideband heater wire in parallel, do you think it would overload the circuit for the heater on the stock wiring? Also what are the wires on the 5 wire wideband for? I know on the 4 wire narrow band it has 2 grounds, a signal wire, and a power wire for the heater.

 

if you are worried about overload, you can use a relay. i dont have a wire diagram for the civic vx, so i dont know what the 5 wires are for.

 

thanks for clearing up the misc facts

Secondly another question I guess that i would like you to clarify is that won't different sensors need to be heated up differently? I would assume different types of sensors have different efficient heating range? And with the autotimer...won't the "resolution" be a little off? You would still need to know how to find what voltage is for what a/f. Since the fjo and the tech edge use the same sensor yet have different settings corresponding to the voltage (well at least thats what I get from the input from the EMS guys) how can you tell?

As for the guy with the apexi idea. Even if it did work how would you plan on idling/driving? I'd assume the ecu would have preset voltage settings for the corresponding a/f ratio?

 

Five wires? Mine has Seven wires and it's from a HX.