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Erratic idle in traffic

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Old Jun 14, 2021 | 01:53 PM
  #11  
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Originally Posted by mjwebb
my eitms has always behaved stable, 1050 rpms, not erratic up and down to 1300+ rpms and I've had it on bikes since its inception
I agree. I’ve had it on previous bikes too and when it does kick in, usually when the bike is really hot, it still idled at a steady rpm. My problem occurs right from the off when the engine is running at normal temperatures.
It is constantly present.
 
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Old Jun 15, 2021 | 02:01 AM
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What have you done so far to diagnose the fault?

Have you checked for codes?
 
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Old Jun 15, 2021 | 05:56 AM
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Originally Posted by mjwebb
well you say Stage 1 so assume it has the AC upgraded..first thing I would check is around there for any leaks, manifold, etc..make sure it's all buttoned up securely..intake leak can cause erratic idle..but could be electronic too, among other things
So my dealership claims they’ve test ridden the bike and not found a fault. Their position is that there’s a clutch switch that automatically raises the revs and that it’s a quirk of M8 engines.
I don’t believe that assertion as I don’t see a single logical reason for HD to build that in as a feature/benefit. It uses more fuel by doing so, so it’s certainly not a ‘green’ or emissions-related thing and I don’t need help not to stall my bike at slow speed!
They claim to have fitted an FP3 to resolve the problem but 1. The problem is still clearly evident. 2. I couldn’t find the FP3 or the box it came in, amongst the box of components I had swapped out when I collected it. 3. They didn’t tell me anything about how the FP3 was set up or how I could set it up myself using the App (if they had of done, the app would be in my phone as I would have tested it worked before I left.
All in all, not a great experience to date and I don’t trust their judgement/opinion on the fault either.
really appreciate your feedback to date folks,
And please be assured it’s not an EMEIS related thing. This ain’t my first Harley so I know what that is, how/when it works and what it sounds/feels like. This is something entirely different.
they say they have checked for air leaks on the intake, but no faults found.
I’m picking it up on Friday and fully expect it not to be running properly.
Can anyone recommend a good HD tech/dealership in South (UK) who can help?
Thanks again all….
 
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Old Jun 15, 2021 | 06:41 AM
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Originally Posted by Gunny110x
So my dealership claims they’ve test ridden the bike and not found a fault. Their position is that there’s a clutch switch that automatically raises the revs and that it’s a quirk of M8 engines.
I don’t believe that assertion as I don’t see a single logical reason for HD to build that in as a feature/benefit. It uses more fuel by doing so, so it’s certainly not a ‘green’ or emissions-related thing and I don’t need help not to stall my bike at slow speed!
They claim to have fitted an FP3 to resolve the problem but 1. The problem is still clearly evident. 2. I couldn’t find the FP3 or the box it came in, amongst the box of components I had swapped out when I collected it. 3. They didn’t tell me anything about how the FP3 was set up or how I could set it up myself using the App (if they had of done, the app would be in my phone as I would have tested it worked before I left.
All in all, not a great experience to date and I don’t trust their judgement/opinion on the fault either.
really appreciate your feedback to date folks,
And please be assured it’s not an EMEIS related thing. This ain’t my first Harley so I know what that is, how/when it works and what it sounds/feels like. This is something entirely different.
they say they have checked for air leaks on the intake, but no faults found.
I’m picking it up on Friday and fully expect it not to be running properly.
Can anyone recommend a good HD tech/dealership in South (UK) who can help?
Thanks again all….
Wow. If you were in the US, I would tell you to find new dealer. Your feelings about this would be correct, you need to have them produce the FuelPak.

My first guess on your issue is an intake manifold leak at the o-rings.
 
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Old Jun 15, 2021 | 07:57 AM
  #15  
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Originally Posted by NorthWestern
Wow. If you were in the US, I would tell you to find new dealer. Your feelings about this would be correct, you need to have them produce the FuelPak.

My first guess on your issue is an intake manifold leak at the o-rings.
thanks!
I’m happy to let them take another look at fixing it, as the bike is still there. They might actually sort it out now I’ve had a heated chat with them about it, but if the problem persists, I’ll be going elsewhere and will post their name on here if another dealership fixes the issue at the first attempt!
 
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Old Jun 15, 2021 | 09:21 AM
  #16  
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Which dealer have you been to at present?
 
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Old Jun 15, 2021 | 10:15 AM
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Two things other than intake leaks come to mind. Make sure your clutch switch is working. Do a throttle position reset. Both have been discussed here.
 
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Old Jun 15, 2021 | 12:13 PM
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Many thanks!
 
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Old Jun 16, 2021 | 08:50 PM
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Yes on the clutch switch and throttle reset. Two of mine did same idle hunting with eitms turned off and was cured by replacing plastic intake manifold with aluminum manifold. Too much heat from air cooled engine and manifold warps. Car manufacturers have been using plastics for intake manifolds for years, but water cooled car engines don't see same temperatures at heads as your bike. My .02 YMMV
 
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Old Jun 17, 2021 | 02:30 AM
  #20  
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Originally Posted by Andy from Sandy
Which dealer have you been to at present?
Hi Andy,
I would prefer not to dis them publicly at this point, as they still have an opportunity to fix it this week.
I will however, point out some of the helpful guidance offered in the forum to date, that has touched on topics and options that they haven’t raised with me to date, which is a bit of a concern.
If you are happy to recommend someone, I would be grateful. I suspect they will continue to assert that there’s no fault and that all M8’s run that way.
 
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