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Misfire and Running Hot on One Side

Discussion in 'V7/V85/V9 Chat & Tech' started by DETRoadster, Dec 20, 2018.

  1. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Oh, right, ECU codes via the FT. Forgot I have that capability now. Duh. Great idea, thank you!
     
  2. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Ah ha, now we are getting somewhere. P0130 and P0136. Both error codes for the right side O2 sensor. I'll poke around the wiring and see if I see anything obvious. Looks like there's some voltage tests I can do as well per the manual. Will also swap them let to right to see if the problem follows the sensor. To be continued....

    Oh, can I simply unplug both O2 sensors and run in open loop for a few miles to see if the misfire goes away?
     
  3. GT-Rx®

    GT-Rx® Administrator Staff Member

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    Yes, good... and not the issue. 130 & 136 are sensor heaters = deleted. Check what I suggested since you just replaced them.
     
  4. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Oh, OK, so those two codes are now normal with the new flash tune? Why only codes for the right side sensor and not the left side?

    Check the plug wire connections to the coils. Got it. I'm becoming a serious pro at pulling this darn fuel tank off!
     
    Last edited: Jan 12, 2019
  5. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Hi fellas, made some progress! Got the fuel tank off again last night and double, triple, quadruple checked the spark plug wire connections to the coil packs. Pulled them off and inspected for any funny business. Put them back on and made sure they not only seated all the way down but I felt the "click" as they made contact and seated. Took it out for another ride and no change. Still misfiring. Gave up and called it a night.

    Out of curiosity this morning I simply unplugged both O2 sensors and hit the road. Huge difference. Rode about 5 miles / 25 minutes. No misfire!!! Feels and smells rich, idle is high, but it goes like a bat outta hell. Got home and pulled trouble codes and have a P0135 which I think is to be expected with both O2 sensors unplugged.

    So I think a couple fresh O2 sensors are in my immediate future.

    @Todd - I'll shoot you an e-mail if you don't happen to see this post. I'm still not clear if the new tune eliminates O2 sensors entirely or just the O2 sensor heaters.
     
  6. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Bringing this thread back from the dead as the problem persists. Left header is reading about 100 degrees F hotter than the right header, at the exhaust port. Bike still slightly mis-firing and stumbling, backfiring, etc. especially when cold and at light throttle input. Seems to run OK at heavy load, heavy throttle.

    I've done the following:

    - New plugs
    - New caps
    - New wires
    - Removed injectors and had cleaned and balanced.
    - New battery
    - New voltage regulator
    - New cam angle sensor
    - Swapped back and forth between stock exhaust and Todd's 2 into1.

    At this point I'm asking myself what could cause one side to run extra hot, that could also cause poor running. I'm starting to suspect a badly burned exhaust valve. Anyone care to check my math on that idea? Am I on to something? I have a leak down tester arriving tomorrow...
     
  7. john zibell

    john zibell Moderator Staff Member GT Famiglia

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    Check valve clearance again if you haven't already. Also look for air leaks in the intake track for the left side. Lean will run hotter.
     
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  8. kiwi dave

    kiwi dave GT Reference

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    You unplugged your O2 sensors and the misfire disappeared. It will run rich without the O2 sensors connected, that is normal.

    Replace that RH O2 sensor, or as you already suggested swap them over to see if the fault moves to the LHS.
     
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  9. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Valves were adjusted about 500 miles ago but I'll check them again. Good idea.
     
  10. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    I thought it did but I'm questioning that. I have Todd's ECU flash and Todd tells me the O2 sensors are ignored with the tune. One thing that is consistent is that it's worse when cold. I do recall that I rode the bike when cold and experienced the issue. Came home and unplugged the sensors, then took it right back out and noted improvement. So I'm wondering if what I actually experienced was just the bike misbehaving when cold and getting better when warmed up. I'll try swapping sensors left to right. I dont think I ever did that and I'm getting right side O2 sensor faults (P0130 and P0136) but Todd tells me that's normal with the ECU flash so I've been ignoring them. Will be interesting to see if they move to the left side.

    I'll let you guys know what comes of the compression and leak down tests tomorrow. Thanks for the advice. Keep those ideas coming!
     
  11. kiwi dave

    kiwi dave GT Reference

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    I have Todd's ECU reflash on a Cali 1400 that I purchased from Todd, and it has the O2 sensors replaced with wideband versions. This is used in conjunction with the Dynajet Power Commander and Autotune. If your reflash doesn't include the Dynajet additions, then yes the O2 sensors are ignored and can be removed.
     
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  12. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Yep I have his famous tune but it does not have provisions for Dynajet. So my thinking something was impacted by the O2s being connected or not was purely in my head. Must have been the difference between the bike being warmed up and not. I sent the modified file back to Todd and he gave it a thorough review, just to make sure there weren't any mistakes, so I know the tune is solid.

    I'll check for intake leaks tonight and do a compression and leak down tomorrow.
     
  13. kiwi dave

    kiwi dave GT Reference

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    If this becomes inconclusive, I would try swapping the O2 sensors. I'm getting the feeling that they are still in service, otherwise why would they affect the misfire when disconnected? Something doesn't make sense.
     
  14. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Definitely no air leaks on the intake. Sprayed starting fluid all over the intake runner, the seal, etc. on both sides. Could not get the idle to change from the spray. Double checked all the clamps and connections. Everything looks good. The plastic intake manifold is in great shape, no cracks, no damage.
     
  15. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    No, I think Todd has them turned off. he double checked the code, specifically looking for that a few months back and confirmed they are indeed off. I really think it was my misperception that it was running better and related to the bike warming up. Still, it's an easy thing to try so I'll swap them side to side, just for fun the next time I'm headed out for a ride.
     
  16. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    Well Gents, the mystery continues. I've done the following:

    1) Removed the GTM flash and went back to stock.
    2) Checked valve adjustment. Both sides, intake and exhaust, were spot on.
    3) Compression test. Both cylinders at 205 Psi +/- a couple pounds.

    I'm going to throw the stock exhaust back on and limp it up to an independent shop (my local dealer went bust). I'm out of ideas.
     
  17. Wisconsin v7 Racer

    Wisconsin v7 Racer Cruisin' Guzzisti

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    Are you sure that anything is even wrong and your not just being paranoid?
     
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  18. DETRoadster

    DETRoadster Tuned and Synch'ed GT Site Contributor!

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    LOL, that's always a possibility! I've not yet been able to find any references to what exhaust temps at the header should be and what sort of differential between the two is considered OK. If someone can assure me that a 60 degree temperature differential between the cylinders is normal, then great!

    As for the misfire, well, that's not normal. I've put 6,500 miles on the bike and this all started about 200 miles ago. It's 100% not normal if we take the previous 6,300 miles I've ridden it as the baseline for what "normal" is.
     
  19. kiwi dave

    kiwi dave GT Reference

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    Have you tried disconnecting the O2 sensors yet?
     
  20. Wisconsin v7 Racer

    Wisconsin v7 Racer Cruisin' Guzzisti

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    I had. Snowmobile with exhaust temp sensors on it and one side was always hotter then the other, it never bothered me. Are you hitting the rev limiter? My buddy road my bike and was a experienced rider he didn't realise he was hitting it. He had the same bike as me but I had Todd's 2 into 1 exhaust and maybe the louder sound through him off.
     
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