2008 ECU swap question

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stealth1

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I am probably not the greatest forum searcher but I have come up empty on this question.

Is there anyone out there with a 2008 model that has replaced their ecu with one from a later model?

The part # for the 2008 unit was one year only.

I have talked to other 2008 owners who have told me that the cure for the 2008's problems can be fixed with a later model ECU.

I have not talked to anyone who has done this.

Is the 2009 ECU even compatible with a 2008 bike?

This is an expensive part to buy just to try it out. I would love to here from someone who has tried it.

Thanks

John

 
Forgive my ignorance but what problems does the 2008 have? The '06 and '07 had some fueling issues but that was supposed to have been fixed from 2008 forward.
Evidently some were fixed but others created.

I believe that is why the 2008 ECU was a one year only part.

Combination of high altitude and cool temps make for difficulty restarting.

I have never experienced this problem east of the Rockies though.

 
Yeah I'm curious too?? My 2008 runs great, the only issue I had was when the idle was too low and it would stall at a stop but that's all fixed when turning up the idle.

 
Interesting now that you mention it.

The two times that I spent the night in Big Bear Lake (~8000ft) outside LA, the throttle would the very on/off the next morning for probably 20 min.

The first time was in Feb and I thought it was just the very low temp overnight. But the second time was in July and it was not that cold overnight.

These are the only times I have had this issue, and also the only time I have spent the night a highish altitude.

 
I believe that is why the 2008 ECU was a one year only part.Combination of high altitude and cool temps make for difficulty restarting.
Do you have threads from this forum on this? I don't remember this one.

I remember altitude issues with 2006 & 2007 only including factory swapping of the CPU. But nothing about cool temps and/or restarting.

I do remember fast starter syndrome that relates to hard starting, but not year specific.

 
I bought my bike new in 2008. At the time I lived in Tennessee and almost all my riding was in the southeastern states.

I only saw the problem once. On a springtime ride to Colorado after shutting the bike off at high altitude to take pictures of the snowpack.

Rode down the mountain and back home and never saw the problem again until I moved to Utah in Dec. 2011.

Now I see it every spring and fall whenever I ride up the mountain east of town. 9000' or higher and 55 or cooler and everything works great until you shut the engine off for a while and then try to restart. Only way to get the bike going is with a huge handful of throttle.

Ride back down the mountain to home, 3500' lower and usually 15-20 degrees warmer, and everything works fine.

I have checked every sensor I thought could cause it and they all look good.

Talked to a couple of other Rocky mountain area 2008 owners with the same problem and the only suggestion I got was replacing the ECU. Neither had done it but one had heard it was the cure.

I'd like to hear from anyone who has swapped his ECU for a later model.

 
I had this cold restart issue for some time with an 09. It was an ECU problem. The fix was a new battery (a new good battery). The symptom was the same as the altitude sickness we had on the 07.

 
First time ever for me...
Chuck35, Really? So even though this is the Automatic Shift model, I should go for the 09-12 ECU?
I'm not certain about the AE, but the later ecu works on my 08 A model.

Taken from page 2 of THIS thread...perhaps a PM to Chuck35 for clarification.

--G

Thanks man! That was some good searching. I have sent a PM to Chuck35.

 
I had this cold restart issue for some time with an 09. It was an ECU problem. The fix was a new battery (a new good battery). The symptom was the same as the altitude sickness we had on the 07.
Forgive me but I'm easily confused. You are saying you had an ECU problem that was fixed by installing a new battery?

 
I have an 09 ecu in my 08 but never had the bike at altitude with the 08 ecu.

In Denver for the IBA event last month I never experienced any issues.

It ran very well up to 14,000 feet on Mt Evans.

I was on the top only an hour or so but restart was fine.

A power commander and full holeshot system is also fitted so YMMV. I'd guess if several 08's have the issue and you know later bikes don't the ecu may be worth it.

 
I have an 09 ecu in my 08 but never had the bike at altitude with the 08 ecu.In Denver for the IBA event last month I never experienced any issues.

It ran very well up to 14,000 feet on Mt Evans.

I was on the top only an hour or so but restart was fine.

A power commander and full holeshot system is also fitted so YMMV. I'd guess if several 08's have the issue and you know later bikes don't the ecu may be worth it.
Thanks.

It's nice to know the newer unit does work on the '08.

My restart problem shows up when the bike has only been off a few minutes, like for a gas stop. And only when it's about 55 or cooler.

Once you get it going it runs fine.

 
Thanks.
It's nice to know the newer unit does work on the '08.

My restart problem shows up when the bike has only been off a few minutes, like for a gas stop. And only when it's about 55 or cooler.

Once you get it going it runs fine.
I had such a stop at Loveland Pass...12,000 ft and restart was fine.

 
My restart problem shows up when the bike has only been off a few minutes, like for a gas stop. And only when it's about 55 or cooler.
I gotta wonder. Last of the summer fuel with low reid vapor pressure?
Nope. This happens every year in spring or fall when the temp is cool enough. I don't ride up on the mountain in winter because of road conditions.

I can ride up in summer with no problems.

Any short stop for any reason and the problem shows up. If I don't stop I can ride my favorite 100 mile loop up there with no problems.

 
Nope. This happens every year in spring or fall when the temp is cool enough. I don't ride up on the mountain in winter because of road conditions.I can ride up in summer with no problems.
I guess my point is the 'shoulders of seasons' is potentially the issue. If you're saying it's fine in the middle of the summer that makes sense. It it's an issue in the fall when it cools down (an you're running on summer fuel formulation), and happens again when they start summer fuel formulation up again but you're going where it's cooler and not summer-like yet....the RVP might be enough to make things sketchy.

I'm just trying to share some other possibiities as I haven't heard '08s in the 7 years on the forum about '08 specific altitude or cold-starting issues before.

 
I rode my 08 in the mountains, up to 6000 ft in April and May, when it was so cold that there were snow fluries, and never had a restart problem.

 
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