Hi all, as per the title, my 2011 848Evo has developed a misfire. It goes great if I open the throttle up, but really doesn't like driving in the 3k to 4k rev range. There's a bit of history that may have absolutely nothing to do with the current behaviour, but here goes... For no better reason than to tinker (aka continuous improvement), I installed exhaust probe eliminators and removed both probes. The bike ran fine, but I would get a periodic engine fault light on. Checking with JP Diag showed both exhaust probes had faults. This is exactly what the eliminators are supposed to prevent. I contacted the supplier and the manufacturer who both told me this had never happened before! Not really believing them, I put the probes back in. Now I've got a misfire. Now, in between all this, my diagnostic cable fried. I got a new one from Lonelec but kept getting faults with the TPS and water temp sensor. These went away whenever the diagnostic cable was connected, but then returned. I narrowed it down to the earth lead on the diagnostic cable. Talking to people with more knowledge of these ECUs, it seems that when the diagnostic cable fries it sometimes takes out the ECU earth sense on pin 21. Connecting the diagnostic connector earth sense line to a clean earth replaces the broken link in the ECU. Does that sound reasonable? So, now the temp indication is working, I replaced the TPS for no good reason, and I've still got the bloody misfire and occasional engine fault light. I have one new exhaust probe I can use to trouble shoot the fault further. The ECU currently reports as below. Has anyone else been through some or all of this?
Frying the diagnostic cable sounds scary, I don't even understand how that is possible. Frying such a cable means you have had a big current flowing when there should be very little current. To me it indicates you have a serious problem somewhere, either in the hardware or in the grounding.
It is not difficult to brick both the ECU and the FTDI cable. Does not require large currents, just inattention.
You can run an external earth wire from the bikes diag connector to the earth terminal on the battery, this will give you the same earth connection you get with the diag cable attached. I've been running my bike like that for years for the same reason.
Hi, EXBV eliminator fitted a few years back. No issues from that. I have now used a spare diagnostic cable to provide a clean earth to the appropriate pin in the bike's diagnostic connector. Note that the exhaust probes do not use ECU pin 29 earth (not pin 21 as I said earlier) so am unsure if or how this is related. The misfire is still there. I have serviced the bike since but it made no difference. I haven't yet put injector cleaner through. I'm open to suggestions....
The rev range where you are experiencing the misfire falls within where both the lambdas and the EXBV have influence. Let me have the map ref for your ECU as displayed by JPDiag.
Hi Chris. I'll get that and attach it today (NZ time). I know I already submitted that to JP to get a licence but can't find it. I'll copy it again.
Do you know if the fault is referring to both lambda probes (as sensors 1 and 2)? The normal protocol for these is that sensor 1 is before the cat and 2 is after but this was designed for cars I suspect. If it is both then it is unlikely to be the probes themselves.
