Gen 2 CPU's... ok to run 2k8 cpu in a 2k6?

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dcarver

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KrZy8 still sick. 2006 CA model. She has a 2k8 engine running with a 2k6 cpu. I'm wondering if it's ok to run a 2k8 cpu to match the 2k8 engine or best to stick with a 2k6 or 2k7 cpu.

2k6 and 2k7 has same part number - 3P6-8591A-23-00

2k8 has different part number - 3P6-8591A-60-00

Suggestions, recommendations, sage advice?

EDIT - on reflection, the 2k6 yamaha had a 17 mpg maximum instantaneous fuel read error that I think was ECU related... as a recall was performed, IIRC.

Leaning toward a 2k7... so as to not get NO FU S.

EDIT -

Assemblies where 3P6-8591A-20-00 is used

2006 FJR13ABS (FJR13AV) - Electrical 1

2006 FJR13ABS (FJR13AVC) - Electrical 1

Assemblies where 3P6-8591A-21-00 is used

2006 FJR13 Electric Shift (FJR13AEV) - Electrical 1

2006 FJR13 Electric Shift (FJR13AEVC) - Electrical 1

Assemblies where 3P6-8591A-22-00 is used

2007 FJR1300A (FJR13AW) - Electrical 1

2007 FJR1300A (FJR13AWC) - Electrical 1

2007 FJR1300AE (FJR13AEW) - Electrical 1

2007 FJR1300AE (FJR13AEWC) - Electrical 1

Assemblies where 3P6-8591A-A0-00 is used

2009 FJR 1300A (FJR13AYB) - Electrical 1

2009 FJR 1300A (FJR13AYCB) - Electrical 1

2009 FJR 1300AE (FJR13AEYCG) - Electrical 1

2009 FJR 1300AE (FJR13AEYG) - Electrical 1

2010 FJR1300A (FJR13AZCS) - Electrical 1

2010 FJR1300A (FJR13AZS) - Electrical 1

2011 FJR1300A (FJR13AACS) - Electrical 1

2011 FJR1300A (FJR13AAS) - Electrical 1

2012 FJR1300A (FJR13ABCL) - Electrical 1

2012 FJR1300A (FJR13ABL) - Electrical 1

 
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I don't have a clue but looking for sage advice from this crew could be interesting. Did you get a cpu with the 08 engine??? I don't remember seeing one. I would think that if that was a potential cause for the current problem it would have showed up before now.

 
I don't have a clue but looking for sage advice from this crew could be interesting. Did you get a cpu with the 08 engine??? I don't remember seeing one. I would think that if that was a potential cause for the current problem it would have showed up before now.
No cpu with the 08, Ray. And it ran great for over 60k miles before not...

 
I thought that the fix for the 17mpg thing was to replace the instrument cluster, not the ECU. On the other hand, the fix for the altitude sickness issue was definitely an ECU swap. As Ray mentioned, if your problem was related to the ECU, I would have expected it from day one after the engine swap.

Does anyone know if any of the ABS function resides in the main ECU (I know there is a separate ABS ECU)? If so, it seems to me that there was an ABS change between '07 and '08.

Running issues are a function of fuel, spark and air. I think you have covered the fuel and spark stuff. Not much to go wrong with the air as long as the filter is reasonably clean. I think I would be leaning toward a sensor failure - what happens if the O2 sensor is sending the wrong data? Air intake temperature or pressure sensors? Throttle position sensor? I don't know what you may have checked or what else might be the root cause. Unfortunately, the ECU is pretty dumb and isn't very good at throwing codes to narrow down problems. Betting its something simple.

Is your California smog canister disconnected?

 
A bit dated post, but I'll give you my experience. I was having FI issues with my '07 and put an '08 ECU in it. It's newer so it must be better, right?
punk.gif


It turns out my problems were unrelated to ECU but I stuck with the '08. That was a couple years ago and I've had zero problems.

 
I chickened out and did NOT get a 2k8 ECU. Found an 07 and it worked. Of course the OEM still works too. The problem was a bad fuel injector rail.

 
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