Rear 02 sensor too rich?

[ravenred92]

So I got a code today saying the o2 sensor was too rich, and the bike started idling like crap, what gives?

does anyone know the cause?

also the volts to the rear 02 sensor is depleted while this light and error is on and all the volts are sent to the front o2 sensor.

 

[Theycallmecrash]

Diagnostically that doesnt sound right. First off how ya checking your codes? You tested for voltage to the sensors how, and exactly what did you read?

 

[ravenred92]

There is a dianoses mode on the bike, hold both buttons on the dash when the bike is off, and while holding those buttons turn the key to "on" and you will have enetered the on diagnoses mode.

 

[ravenred92]

Also, I know it doesn't sound right but the 02 rear sensor error code 151 is too rich o2 sensor and it idles like crap so I don't have a clue, especially since all 8 volts are going to the front o2 sensor (they both should maintain 4 volts.)

 

[Theycallmecrash]

[confused]

Yep, 1125s elude me.

 

[ravenred92]

fak....I might have bought a pretty lemon..

 

[ravenred92]

well maybe this can shed the light on some things, when I unplugged the rear o2 sensor I get a constant 4 volts to the rear o2 sensor, so it leads me to believe that the rear 02 sensor has failed, and until I can put it in the shop I am unplugged both 02 sensors. which seems to temperarily work.

 

[ravenred92]

Wow, I rode the bike with both 02 sensors unplugged and knock on wood, didn't change anything and if anything it made the bike idle better and more consistently..I know that the bike ecm runs off of a fuel map, and I also know that without the 02 sensors that the bike would dump more fuel, but here is the deal, I am also running a drummer exhaust so IDC if that is compensating but the bike idles WAY smoother w/o the 02 sensors plugged in..and there is no loss in power, no bogging etc etc...

 

[2hy2ride]

You should read the chapter in the ecmspy tuner guide II about tuning without o2 sensor even if ur not gonna tune just good lit And maybe keep an eye on the rear plug to make sure it doesn't get gummed frum being way rich. Do you have a way to read the afv correction rate or set it?

 

[ravenred92]

Not necessarily at the moment, but I plan on replacing the 02 sensor and putting and ebr ecm on it, but that'll be fore another month or so because there's noway I am replacing it myself, gonna take it to a harley shop and pay them to do it. So this will just have to do~

It's a buell, I am sure it won't just blow up on me

But enlighten me~

 

[ravenred92]

I just realized that fuel injection without 02 sensors are just like carburators running rich....wow

 

[d_adams]

So you're running a drummer with a stock ecm, right? Check the AFV's and see where they're at, look in the diag on the cluster. Every aftermarket exhaust out there for 1125's will make it run lean, some more than others. Forcing the ecm to run on the base map by unplugging the O2 sensors will keep it from "hunting" for the right fuel mixture, but it's not an ideal fix, especially with a stock ecm.

You can get at the rear O2 sensor relatively easily, I think it takes maybe 20 minutes to change it out. Definitely get the race ecm asap, that will help the bike more than anything.

 

[ravenred92]

Mr adams please refer back to my new topic.

 

[d_adams]

Didn't realize you started a new topic.