Starts, rough idle and stalls (2010 GS)

[Rocky Mountaineer]

I've a 2010 30 Yr Anniversary GS, near 16k on the clock. In the last few months she starts, but burps farts stalls unless you run a hot throttle to warm up the engine. BMW have had her apart, checked the plugs ... but she's warm when she gets to their place and I'm loathe to let them have her overnight to check. When she's cold, she runs like she has shit petrol or dodgy plugs.

Thoughts? Similar experiences?:

 

[Schtum]

If it's running as bad as that, you'd expect it to have thrown a fault code or two. I take it you've had it into Clark's in Aberdeen? I'd have thought they have hooked it up to the machine and read the codes.

However, my hunch would be that one or both lambda sensors are knackered....

 

[Rocky Mountaineer]

If it's running as bad as that, you'd expect it to have thrown a fault code or two. I take it you've had it into Clark's in Aberdeen? I'd have thought they have hooked it up to the machine and read the codes.

However, my hunch would be that one or both lambda sensors are knackered....

Good thought, but I did take it straight to John Clark's after it very nearly stalled going 3/4 the way around a roundabout (that wasn't fun). No fault codes, and Craig stripped out the plugs and didn't see any evident fouling. It was fine this morning, so seems interimittent failure.

They replaced the corroded heads on Weds, thought maybe Craig might have seen something then but it was just as bad when picked up. You hold the throttle on in neutral and the engine revs up and down and farts and burps...

Not fun.

 

[Pukmeister]

If not Lambdas then next guess is TPS.

 

[polisher]

TPS

If not Lambdas then next guess is TPS.

I had exactly the same problem. Changed the plugs, checked the wiring etc no joy. Southport Superbikes put it on their diagnostics & it was the TPS. £96 for the part, took me 5 minutes to fit it & it cured it

 

[Rusty Bolts]

From the symptoms described its looking more like the TPS. I have had similar symptoms but not as severe and bought a used one from Motorworks for about £40. Problem solved.
You could eliminate the lambda sensors by disconnecting them to see if it makes a difference?? Never tried it myself but do you not remove the lambda sensors with some after market headers?

 

[Rocky Mountaineer]

I had exactly the same problem. Changed the plugs, checked the wiring etc no joy. Southport Superbikes put it on their diagnostics & it was the TPS. £96 for the part, took me 5 minutes to fit it & it cured it

Good thought. I'm offshore North Sea this weekend so dropped the GS into John Clarks until Monday for MOT, service and to fix the cold idle issue. Craig thinks may be plugs as a result of poor quality fuel, but will prompt him on the TPS to see if that was considered.

Fingers crossed for a Monday success!

 

[Bendy toy]

Starts ok from cold but runs rough when hot and consumption goes up. Suspect the Lambda.

Injection is set rich by default. Lambda is ignored until engine hot enough then it switches in and injection adjusts accordingly. When Lambda fails the affected cylinder runs rich so easy enough to spot.

Runs weak when cold could be lambda is working fine bit switched on immediately. Check the engine temperature sensor is not reading high.

 

[Kritou]

This may be worth a read ......

http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=845878#Post845878

 

[bhud]

I had a similar problem.
Mine struggled to get going but limped into JC. We thought it was dodgy fuel as it hadnt been run for a year but it was the Fuel pump controller change out and fine.

 

[Bendy toy]

Bad fuel often gets blamed but as @bhud says even 12 month old fuel wasn't causing his problem.
UK fuel is (almost) never the real issue**. 99.8% of the time it's something else.

Even Asda yobbo brand comes from the same silo as all the other petrol.

 

[Rocky Mountaineer]

If it's running as bad as that, you'd expect it to have thrown a fault code or two. I take it you've had it into Clark's in Aberdeen? I'd have thought they have hooked it up to the machine and read the codes.

However, my hunch would be that one or both lambda sensors are knackered....

Gutted. Just off the phone with JC. They're saying they've had the bike for 4 days and there's nothing wrong with it. No fault codes, no obvious faults during scheduled service, no issues on starting or riding it around ABZ.


For this level of investment I have a motorcycle that I'm not comfortable driving to Dundee much less to the ends of the earth. Cold idle is all over the map, stalls around roundabouts, loses power at speed...but there is apparently nothing wrong with it.

Disappointing. I could go to BMW and pick it up now, but I'll leave until tomorrow. I have more confidence in my 1958 Triumph T100, but at least that's running properly...

 

[GSgirl]

Hi Rocky - Friend of mine had the same problem but with an '08. What I have read is that some cases were solved by replacing the camshaft position sensor(s). It seems a problem with these doesn't show up on readout unless it happens to be in the exact position where the problem occures. Needle haystack. Hope this helps..

 

[Bendy toy]

It sounds like the dealer has plugged in his computer, but not actually ridden the bike from overnight stone cold.

 

[Rocky Mountaineer]

1200GS: it's not funny anymore

Hi Rocky - Friend of mine had the same problem but with an '08. What I have read is that some cases were solved by replacing the camshaft position sensor(s). It seems a problem with these doesn't show up on readout unless it happens to be in the exact position where the problem occures. Needle haystack. Hope this helps..

Two days after collecting the GS, the idle problem returns. First start was fine, I rode the bike into work. Back on the bike to ride into the city 90mins later, idle all over the place and the engine stalled twice. When it came to temps it was fine, and then fine later.

This is really not funny anymore. Took it into local Triumph dealer to enquire trade value and to have a look at Explorer. I'm frustrated, but appear not to be that frustrated yet...

I have an expensive but faulty motorcycle that BMW can neither diagnose nor fix at the moment. Search for needle in haystack continues, apparently.