O2 sensor and low voltage

[RPG]

My '04 RT (106k miles) was running pretty well until a couple weeks ago when it would stall at idle intermittently. And it wouldn't idle at all while cold, unless the throttle was cracked open.

 

For the hell of it, I pulled the pink coding plug and rode another 1000 miles, and it only stalled once at idle.

 

I hooked up my GS911 tonight to plot some values, after doing a TPS re-learn (remove fuse 5), re-connecting the pink stock coding plug, and warming the bike up to five bars.

 

Interestingly, although the GS911 main display shows about 14.4vdc at idle, the log says different (max 12.03vdc). And also important, I'm seeing a steady 12mv steady voltage on the O2 sensor (brand new sensor, replaced last winter), where I would expect the voltage to swing between 200mv and 600mv.

 

I had a AFxied installed until this spring, where at a track day, the bike wouldn't rev past 4 grand and removing the AFxied seemed to solve the problem. (I know doing that meant it went open loop).

 

Any guidance would be appreciated.

2004 R1150 RT log 2019-08-23.csv

[dirtrider]

29 minutes ago, RPG said:

My '04 RT (106k miles) was running pretty well until a couple weeks ago when it would stall at idle intermittently. And it wouldn't idle at all while cold, unless the throttle was cracked open.

 

For the hell of it, I pulled the pink coding plug and rode another 1000 miles, and it only stalled once at idle.

 

I hooked up my GS911 tonight to plot some values, after doing a TPS re-learn (remove fuse 5), re-connecting the pink stock coding plug, and warming the bike up to five bars.

 

Interestingly, although the GS911 main display shows about 14.4vdc at idle, the log says different (max 12.03vdc). And also important, I'm seeing a steady 12mv steady voltage on the O2 sensor (brand new sensor, replaced last winter), where I would expect the voltage to swing between 200mv and 600mv.

 

I had a AFxied installed until this spring, where at a track day, the bike wouldn't rev past 4 grand and removing the AFxied seemed to solve the problem. (I know doing that meant it went open loop).

 

Any guidance would be appreciated.

 

 

Evening Rick

 

Yes, I see the low steady o2  voltage with no crossovers.

 

It does start out seemly working OK then goes low & flat. Might be a bad o2 sensor, or you really are going lean.  

 

You didn't solder the wires in  the o2 harness when you installed the new o2 did you? (soldering will block the o2 reference air & they flat won't work correctly)

 

Is the o2 sensor pig tail hanging down on the hot exhaust?

 

Is the green/white wire in the o2 sensor connector getting 12v with engine running (that is the o2 sensor heater power) 

 

Kind of a pain but you might try completely disconnecting the o2 sensor, then remove #5 fuse for 5 minutes, then re-install the fuse & do a new TPS re-learn.   

Then ride the bike looking for idle stalling & general operation & ridability.

 

If it runs better & doesn't stall then you probably have a bad o2 sensor or somethin wrong with the o2 sensor wiring/circuit. Maybe look for water/moisture  in the o2 sensor connector or ???? 

 

 

 

 

 

[RPG]

14 hours ago, dirtrider said:

 

Evening Rick,Good  morning D.R.,

 

Yes, I see the low steady o2  voltage with no crossovers.

 

It does start out seemly working OK then goes low & flat. Might be a bad o2 sensor, or you really are going lean.  

 

You didn't solder the wires in  the o2 harness when you installed the new o2 did you? (soldering will block the o2 reference air & they flat won't work correctly)I didn't do any soldering. The sensor I got plugs right into the existing connector.

 

Is the o2 sensor pig tail hanging down on the hot exhaust? It is not. I have it routed to come up near the transmission, away from the exhaust and as far away from the lower right H.T. spark plug wire as possible.

 

Is the green/white wire in the o2 sensor connector getting 12v with engine running (that is the o2 sensor heater power) I will check that. Thank you

 

Kind of a pain but you might try completely disconnecting the o2 sensor, then remove #5 fuse for 5 minutes, then re-install the fuse & do a new TPS re-learn.   

Then ride the bike looking for idle stalling & general operation & ridability. I'll need to remove the Tupperware to do that so stay tuned.

 

If it runs better & doesn't stall then you probably have a bad o2 sensor or somethin wrong with the o2 sensor wiring/circuit. Maybe look for water/moisture  in the o2 sensor connector or ???? I'll investigate that. Thanks again.

 

 

 

 

 

 

[dirtrider]

Morning Rick

 

Check you PM's-- Roger sent me a PM with some info on your problem & I passed it on to you along with some other info.