02 sensor

[4t9erfan]

i keep getting 02 sensor codes on my 08 ultra had it at the dealer 4 times now they replaced one ran ok for about a month came back took it back they said had a broken wire they fixed that came back the
y told me i needed a stage 1 download got that it came back they said it was my computer they put in a new ecm and now it is back!! i have basic vance and hines muffler and a air kit i just put the air kit on the mufflers havr been on almost two years only benn having the problem about 8 months
(help)

 

[glider]

Did they tell you what was wrong with the first 02 sensor? Possibly it may be the gas you are using fouling the sensor?

If they did the download and charged you for it and it didn't help, have you asked them for a credit on it?

 

[4t9erfan]

i use chevron prem
they didn't tell me anything on the sensor

 

[Hoople]

i keep getting 02 sensor codes on my 08 ultra

What is the code number(s) that you keep seeing.
Do you have ANY type of added fuel controller on the bike. Do you have Nightrider Xides on the bike. Have you seen any other codes besides the O2 codes.

 

[4t9erfan]

i get a p0132 and p0152 i do not have niterider xides
a rear brake switch and a front

 

[Hoople]

a rear brake switch and a front

A P0132 is the Front cylinder running rich for too long of an operating time. A P0152 is the same but only for the rear cylinder. The ECM is not seeing the O2 sensor toggle from lean, back to rich, back to lean etc.

Anything that would cause the engine to have a FIXED A/F ratio lower than 14.3 for an extended period of time will toggle those 2 codes.
Thing such as an out of calibrated cylinder head temp sensor, out of calibration MAP sensor, excessive fuel pump pressure, lack of air flow through the air cleaner, poor cylinder combustion due to ignition problems etc etc. You get the picture. Anything which would push the A/F ratio to the rich side (and keep it there) would do it.

But first the service tech needs to confirm the theory using a scope on the O2 sensor outputs. If the O2 sensor output waveform does not toggle rich,lean,rich,lean over and over again with around a frequency of 1HZ,,, (60 times a minute) that is your problem. The Digital Tech the dealership has should show an O2 sensor toggle action.

I doubt a Stage one MAP would help. That would only push it more to the rich side.
Since BOTH cylinders are running rich, I would doubt both injectors are bad or leaking. Since it is BOTH cylinders, you would have to have multiple issues with the wiring harness for this to happen. So my guess is that the wiring to the O2 sensors is OK.

Need more info to narrow it down.
You did not answer the question about having ANY type of enrichment fueler.
You did not say if you have seen ANY other codes other than the O2 codes.
What does "a rear brake switch and a front" mean? Codes for switches?
Other than having the codes, how does the bike run? Does it pull hard without a miss?

 

[4t9erfan]

i don't have any type of enrichment fueler
the only other codes is the brake light codes
the bike runs good it just pops alot after i get the codes if i clear the codes and reset the computer it runs good it does pull hard without a miss it only has 10500 miles on it

 

[Hoople]

OK. They probably are, but the very first thing that needs to be checked is to confirm that both O2 sensor are seeing a Rich mixture even when they should NOT be. Hold the RPM at 2500 in neutral. At that RPM and intake manifold pressure, the ECM is in closed loop mode and the O2 sensors should be toggling. The A/F ratio should be stoich at that point and with E10 fuel you should see an A/F ratio of 14.3 (maybe even leaner) using an exhaust analyzer.

Now if you see that the engine is running rich (pegged sensors) when it should not be, you start hunting for the reason. Keep in mind that the reason must affect both cylinders. Something as simple as a stuck fuel pump pressure regulator would push too much fuel into both cylinders. An out of calibration map sensor could also do it. A TPS sensor that tells the ECM "more fuel" when butterfly position does not correspond with more oxygen. Things like that....

I am probably making it sound more complicated than it really is but after 4 attempts at having it fixed, I want to give you a little info about the process behind it all.