1200 GSA rough idle/stall problem
 

Hi. I'm hoping there might be someone here who can help.

2007 GSA. It's developed a rough idle. If I add a Power Controller, after 5 or 10 minutes of riding, once the engine is up to temperature, this happens:

YouTube - ‪07 GSA rough idle issue‬‏

It's been checked with a GS911 - nothing - and the coils have been checked and are fine. And it's recently had its 36k service and all was ok apart from the rough idle/stal.

So I'm drawing a blank and getting frustrated as I'm off on a 6,000 mile trip in a couple of weeks. Can anyone help diagnose the problem?

First of all RE: "it's recently had its 36k service and all was ok apart from the rough idle/stal."
Surely you should have told your dealer then if you've paid for a service and this happens?:blushing:

In no particular order, I'd check - to try and isolate the problem
1- your power commander -
has it been installed correctly?
is it tuneable?
is there corrosion/water in the connectors? (classic fault)
Importantly- does the bike run correctly without it?

Check point 5 below first!

2- Bridged Spark plug?
3- When was last time you have the valve clearances done?
4- Air filter - last checked/changed?
5- Throttle cable seating - easily disturbed when the tank is removed-the cables are attached to the throttle bodies
6- alternator output?

Thanks for your response, Bertrand. The service was done privately (by Steptoe on the ukgser forum) who knows his stuff and the idle issue has him stumped.

1. Without the PC it doesn't stall but the idle is rough. Here it is on video, without the PC:

YouTube - ‪07 GSA rough idle‬‏

The PC was installed correctly, has a custom map and I've greased the connectors. I thought it was a PC problem at first and Dynojet sent me a replacement, but the same thing happens. For some reason, though, it's worse with the PC as you can see from the first video.

2/3/4 - all taken care of at the last service (2 weeks ago.)

5. Looks OK.

6. Don't know.

Looking around other forums, things that might be factors are
Stepper motors
Crank sensor
Vacuum leak

Do any of those sound likely in this case? The intriguing thing is that the PC makes it worse but is not the source of the problem!

When you had the GS911 connected, did you cycle the stepper motors? Any difference?

Yes, they were reset, but then gradually moved up one side followed by the other when the engine was restarted. The guy who did the service said he'd not come across this before. All he could think of was the coils, which he checked and they are fine apparently. That's as far as I've got.

Without knowing how the coils were checked, I would swap the main (straight) coils between cylinders and see if anything behaves differently, since that is easy to do...

He disconnected the lower ones, then the uppers to see if there was a dud on either side, but didn't swap them over. Is that worth doing?

Again, that what I would do since it is easy to accomplished. Also, it looks like you have done pretty much everything else.

Sometimes intermittent, weird stuff can be identified when fiddling with it, i.e. broken cable leads or bad connections.

You did say that you removed the power commander and the problem still persisted - right? After the power commander was disabled, did you disconnect the battery to reset the electronic? Again, just a stab in the dark...

I took it into a BMW dealer earlier today and here is the report:

https://docs.google.com/viewer?a=v&p...1ZTJk&hl=en_GB

So, a blank, and an expensive one. A bit frustrating - I have no idea where to go from here.

Hmm, ...nothing odd I can see on the dealer's report with my limited knowledge.

I went back to your first- and second video, i.e. with PC and without PC respectively.

I could not really detect a "rough" idle from the second video (without PC). However, you would know best comparing it to "pre-service" idle.

When installing the PC, how much time is required to run the engine to self-adjust the ECU to the different air/fuel mixture? Does it make a difference in the idle, if you ride the bike for 15-20 minutes (until at operating temperature)?

If not already done, you might want to consider cross-posting at ADVriders "GSpot" section. The have a lot of folks on there with good technical knowledge. Sorry, I can't be of more help...:confused1:

I don't know the answer to your question. I have a custom map, not the autotune device, so the PC's input is pre-defined. I don't know how much time it takes the bike to adjust. Another rider has suggested that adding the autotune module would help sort out this issue.

In the meantime I've ordered and installed an accelerator module, which gives the smoothness of the PC via a different route, and so far hasn't led to any stalls. The basic problem with the idle remains so I'm resigned to living with it, or possibly to getting a new TPS to see if that's at fault. I read somewhere over in the Adv forum about someone replacing this, even though diagnostics said it was fine, and a very similar problem to mine sorting itself out after that.

M

Same here !!!
 

High there, my bike has been doing this intermittently for years now and have just been riding around it by catching the bike just before idle on the accelerator. it then idles fine.

id like to fix it but with kids, marriage and cutbacks i don't want to throw money at it.

Steptoe usually services the bike and he hasn't been able to fix the problem either.

I also live in London and do not get any fault codes....???

I think I've narrowed it down to either TPS sensor or Coil plugs.... all are bonkers money .... Any help would be appreciated

Scott:innocent:

TPS
 

Oldish post this but did you sort your issue..?? My mate had a similar issue earlier this year and although a retired Porsche mechanic he was pulling his (what's left) hair out over a resolve. Using a 911 test rig to help, nothing came up, finally narrowed it down using logic and proved to be the TPS....