'10 xb12xt CEL

[cdh4088]

Hi there,
on my 8000 mile 2010 xt, I am getting 3 fault codes and an odd running condition,
Bike starts and runs great until its warmed up, then it loads up, backfires a little. Then the CEL comes on and just as soon as it does, it clears up instantly and runs great until I shut it off and start again.
Three codes in ECM, its an EBR unit.
21, 33, 37.
the fuel pump code 33 seems to be the most important, but my symptoms dont really sound like a fuel pump. Ive checked the external wiring, and the pump cycles as it should when the run switch is cycled, so I dunno.
If the fuel pump is weak, will the ECM cut the horsepower down to compensate? because just as soon as that CEL comes on, it runs fine again.

If I replace the fuel pump, whats the best part available? buy the whole shebang from Hardley, or fit an aftermarket pump?

thanks in advance

 

[user_deleted]

1-you're also receiving IEV fault code. check both the control unit which sits atop the air box inner cover as well as the muffler valve for proper operation. i check both by removing air box outer cover and turning key on...then run switch to on and watch for proper cycling and cable movement.
2-tons of posts on here by very knowledgeable board members on inexpensive pump alternatives......less than 1/2 the price of dealer option.
3-i'm no ecm expert but not aware of any "limp-home mode" feature built into your ecm to compensate for loss of fuel pump pressure.
4-your 2010 has twin O2 sensors. front easy to access....rear a bit more work but do-able. if faulty they will dump code #13 into your ecm but i've seen contaminated ones cause your symptoms. sometimes a quick cleaning with toothbrush and sea foam or isopropyl alcohol restores their accuracy.

 

[ReadyXB]

the fuel pump code 33 seems to be the most important, but my symptoms dont really sound like a fuel pump. Ive checked the external wiring, and the pump cycles as it should when the run switch is cycled, so I dunno.

If your pump has an intermittent short, the symptoms may not seem like a fuel pump issue. But code 33 says you have a short either to ground or to +12V. The short could be inside the frame/tank.

Based on the symptoms described, I would guess an intermittent short to ground on the Brown / Yellow wire which, according to the diags manual, would cause the pump to run continuously (only while shorted, of course). The result would be periods of having too much fuel pressure. Check out this thread; it may help visualize what you're dealing with regarding the wires:
http://www.buellxb.com/Buell-XB-For...ityX-XB12Scg/Troubleshooting/Fuel-light-issue

If the fuel pump is weak, will the ECM cut the horsepower down to compensate? because just as soon as that CEL comes on, it runs fine again.

Not to my knowledge. The only pump duty cycle adjustments that I know of made by the ECM are based on RPM. I would love to see a datalog captured when the CEL comes on and then it starts to run normally. I could tell you for sure then.

Three codes in ECM, its an EBR unit.
21, 33, 37

If we don't believe in coincidences, you might have a chaffed spot in your wiring harness. Code 37 means either a short-to-ground, open, or high-short condition. 'Open' is easy to check by re-seating the speed sensor connector. If the code is still set, you could have a harness short or a bad sensor. Neither are more likely than the other on a 2010 model.

Code 21 is for the interactive muffler actuator. I see that you are looking for a Spec Ops muffler in your other thread, so you may already know this. What muffler is on the bike?


Do you have a service manual? It has flow charts for diagnosing all of the above problems.

 

[user_deleted]

^^^^^ great info as usual ready. didn't think about the chafed wires/short to ground but that would certainly increase his fuel pressure and be possible culprit.

 

[ReadyXB]

^^^^^ great info as usual ready. didn't think about the chafed wires/short to ground but that would certainly increase his fuel pressure and be possible culprit.

Thanks, and same to you! I probably need to get it out of my head that a 2010 model is still "new" and shouldn't yet have fuel pump or sensor issues. It is 5 years old.

 

[cdh4088]

Ive got the ops muffler on, ebr ecm with actuator enabled. Ive done a cable adjustment, and the sweep test, and all looks good. Ill check the vss mounting next time Im under it, the speedo never misses a beat.

So without any external wiring issues, I should be replacing the fuel pump for that 33 code? The bike did sit a year or two before I bought it.

Ive got the bluetooth parts ordered to build my own ecm droid box, Im looking forward to using that.

 

[ReadyXB]

So without any external wiring issues, I should be replacing the fuel pump for that 33 code? The bike did sit a year or two before I bought it.

In the absence of external wiring issues, I would recommend removing the fuel pump for inspection before ordering any new parts. There could be chaffing on the wires inside the frame that connect to the pump motor, or even a bad solder joint at the connector.

 

[cdh4088]

ok, I managed to clear all the faults, and have come up with a rear 02 sensor always lean.
whats the usual suspect?
dirty injector?
goofy sensors?
is there a DIY injector cleaning procedure?
Ive had great luck using seafoam fuel additive in cars before.