Hey guys, quick question. With the autometer cobalt air/fuel ratio guage (autometer part #6175) is it necessary to buy the O2 sensor kit (autometer part #2244) or is there a sensor already in the car that can be used? I have an '04 WRX.

it's electric narrowband, so you can use the stock rear O2 sensor signal from the ecu...

but that doesn't mean you should use it. the existing sensor is not accurate for O2 readings, you need a dedicated sensor in your exhuast manifold to get any usable reading.

but you can install it and it'll look pretty and flash.

Thanks a lot. . .looks like i'll have to save up some money and buy the O2 kit. . .just a follow up question, what's the difference between a narrowband and a wideband sensor? Is one better than the other?

just a follow up question, what's the difference between a narrowband and a wideband sensor? Is one better than the other?

:confused:
bump

Thanks a lot. . .looks like i'll have to save up some money and buy the O2 kit. . .just a follow up question, what's the difference between a narrowband and a wideband sensor? Is one better than the other?

Narrowbands are just used to check cat efficiency (only accurate near stoich). Widebands are used to tune (accurate in a much bigger range).

Your autometer gauge will just be a light show. It won't show any useful information.

one operates on a 0-1volt spread, the other on a 0-5volt spread. the wideband is the only one accurate enough to use the data in terms of running rich or lean and how to tune to adjust it.

a narrowband just isn't useful enough. i took mine out.

ooooo. . .i get it.
I'm gettin it more to show off to friends rather than tune since i don't really tune my car myself. I picked the gauge b/c it looked the best. . .but thanks a lot, i've been enlightened. :D

Everyone always says a narrowband sensor is no good, but you do realize the the ecu bases almost all its fuel calculations on the reading from teh o2 sensor right?

I have an autometer air/fuel guage in conjunction with my egt guage its pretty dam accuratte for tuning my safc.

Jay

My autometer is wired into the 02 sensor. Mbiker is correct in saying it is a lightshow....at idle it slowly bounces back and forth, like it can't make up it's mind, but at wot and normal highway driving it reads pretty steady for me. It seems anyway(from my limited experience) that it stays in the far green when the utec is saying I'm running rich, so it must be working. I don't use it to tune with though, it just makes me feel comfortable when I floor it, to see that its on the rich side. :)

thanks for all the feed back guys. . .another follow up question tho, if i get the extra O2 sensor, where is the best place to mount it? near the old sensor or somewhere else?

thanks for all the feed back guys. . .another follow up question tho, if i get the extra O2 sensor, where is the best place to mount it? near the old sensor or somewhere else?

the existing sensor is not accurate for O2 readings, you need a dedicated sensor in your exhuast manifold to get any usable reading.

but you can install it and it'll look pretty and flash.


If you don't have much mechanical experience, I'd suggest you have a shop install an O2 bung for you.


Mick

haha, thanx, maybe next tinme i'll read first :D

Everyone always says a narrowband sensor is no good, but you do realize the the ecu bases almost all its fuel calculations on the reading from teh o2 sensor right?

I have an autometer air/fuel guage in conjunction with my egt guage its pretty dam accuratte for tuning my safc.

Jay
Hi Jay
Are you sure about that? I believe the o2-sensor on a stock car does not change the fuel calculations that much. The maf or map-sensor is the major sensor when the ecu is changing the fuel.

/p

- Handsdown,
you said to use the rear o2 sensor. why do that? the rear o2 sensor is there just to make shure that the cats are working properly. any way, i tried to hook mine up to the front o2 sensor and i coulden't get it to read. it just went to full rich and thats it. the lowest voltage comming out of the conector is somewhere around 3.4v. way to high for the guage. the sensor its good and the car runs fine. the only thing that i can think of is that the o2 sensor is a titania type of sensor that changes a 5v referance from the ecm. the guage is for a zirconium o2 sensor that produces between 0 and 1 volt. im stumped!

Hi Jay
Are you sure about that? I believe the o2-sensor on a stock car does not change the fuel calculations that much. The maf or map-sensor is the major sensor when the ecu is changing the fuel.

/p

The factory ECU changes the fuel trims (both long and short) during cruising, and slight throttle. As soon as you enter WOT, or open loop fueling, the O2 sensors are ingored and only MAF and rpm are used for fueling.

no, you need five inputs to go into closed loop; mass air, rpm, coolant temp, throttle position, and o2. in open loop the o2 is not used. the car needs to warms up before it goes into closed loop. coolant temp determins that. but that still doesent explain why the guage wont work. i think im gunna get rid of it and buy a clock. the clock is a lot more usefull!

-mbiker97
you are right the ecu does make the fuel decisions. i just listed the five inputs that it need to make them.

So will the 6175 gauge not work with a wideband O2 sensor?

also, closed loop fueling isn't where you can damage it. it is open loop WOT that will blow up things, where a narrowband is useless, and the ECU doesn't use the stock O2 anymore.