Running rough, won't idle, loud thumping

[rup5555555]

I just tried a TPS reset but no change.

Then pulled out the primary plugs and checked for a spark - no spark on primary left or right!!!!

It seems to be running just on the secondary plugs - didn't have time to pull them mind. But it runs better without the primaries plugged in!

What does that indicate?

 

[Pukmeister]

I just tried a TPS reset but no change.

Then pulled out the primary plugs and checked for a spark - no spark on primary left or right!!!!

It seems to be running just on the secondary plugs - didn't have time to pull them mind. But it runs better without the primaries plugged in!

What does that indicate?

IIRC it only uses one spark plug at low revs, as revs/load rise the second plug comes into play. Of course I could be wrong.

You could try measuring the resistance of the stick coils with a multimeter, I don't have any figures to hand though plus they tend to be fine when checked but break down under load conditions.

 

[rup5555555]

hi Adam
thanks for for all the help on this!!!! Did I test the spark incorrectly? I was thinking I was on to something...

Should I rev the hell out of it to test the plugs? Should I be able see the spark?

 

[DrFarkoff]

hi Adam
thanks for for all the help on this!!!! Did I test the spark incorrectly? I was thinking I was on to something...

Should I rev the hell out of it to test the plugs? Should I be able see the spark?

DO NOT REV THE HELL OUT AN AIR COOLED ENGINE WHILST STATIONARY!!

Stop pissing about with it and go find someone who knows what they are actually doing!

If you keep messing with it you when you have no idea what the feck you are actually supposed to be doing...................You WILL damage it more and you will end up paying dear for it!

Sorry to Be Blunt but I've probably saved you money by telling you all of the above!

Good Luck with it and do let us know what it was!

EDIT

If you take off the seat is the thumping noise coming from the airbox just in front of the battery?

If so I suspect possibly a burned valve but over the internet I may as well try guessing what colour it is with my eyes closed

 

[rup5555555]

thanks jay, i will try that. I have ridden this bike around the world and know it well but just not this problem...

 

[DrFarkoff]

Fair Play to you for riding around the world on it, a brave person for taking a 1200!

What is your level of mechanical ability? Could youservice the bike yourself?

Re the spark plugs, did you ground the threads on the frame or an exposed bolt while trying or just in the coil thing in mid air? The current travels down the coil to "jump" the gap at the lower end of the plug but requires the plug to be earthed or grounded to the frame.

If you hadn't them grounded out then the test wont work and be careful because theres a lot of volts in there ( a faulty hall sensor made the one I was fiddling with start sparking for about 5 seconds, An enlightening experience I can tell you!)

I can't understand why the bike won't idle as the idle sequence is controlled by the two stepper motors on the throttle bodies

Certainly if the mixture is very bad then it could be the throttle position sensor which would be giving false information to the ECU and then the fuel is either too much or too little

You could run the old motors with the TPS disconnected to do tests (as the ecu goes to a default value if it doesn;t read anything I'm not so sure about the new ones

A compression test woould probably be enlightening especially if theres very little pressure on one side? it would certainly rule out mechanical failure rather than supposition over whether or not the smoke is staying inside the cables!
Have you ever noticed that if the smoke escapes from inside the wires, then the electrical things stop working?

 

[rup5555555]

I do service the bike myself and see myself as technical but not knowledgable on all matters. I have not tested a plug before so did not know how to ground it - thanks for this, I'll try it tomorrow. This is a good learning experiance as I plan to ride to India in late summer ...

...no smoke from the wires. I do have the bike booked into a dealer but the earliest they could is late next week and I need the bike before that.

Cheers Rupert

 

[DrFarkoff]

...no smoke from the wires.

Sorry it wasn't meant as a piss take at you, I was just relaying my friends Jovial wee theory on electrics, electronic and all forms of elec"trickery"

He reckons the cable factories fill the wire with smoke to make "things" work, as when the smoke escapes the "things" stop working

Anyone with a GS911 in "Ruperts" area??

What age is the bike? Do you not have BMW assist as an option?

Good Luck with whatever the Problem is

 

[Fredrik]

Hi
I had the same problem with my 07 .The TPS was broken.Warranty claim.They had to change the sparkplugs at the same time.Dont ask me why
Fredrik

 

[rup5555555]

tested the spark again with grounding and it sparks ok

I also looked at the TPS and it is doing something because when i remove it the bike does not rev at all. If i move it manually it changes the throttle response

 

[Boffer]

Check fuel pump relay hasn't corroded. Same intermittant faults mime showed for several weeks before not starting at all.

Won't idle, poor throttle response, knocking, running hotter, hesitation - sound familiar?

Check out fuel pump threads.

 

[Pukmeister]

Check fuel pump relay hasn't corroded. Same intermittant faults mime showed for several weeks before not starting at all.

Won't idle, poor throttle response, knocking, running hotter, hesitation - sound familiar?

Check out fuel pump threads.

Why didn't I think of that.

If the fuel pump isn't delivering enough fuel it could give you the symptoms you describe. Thinking back, mine did the same (once) a few weeks before my FPC died on me. I originally thought the TPS reset cured mine, but it was probably just coincidental.

Good call.

EDIT: Best to remove the FPC anyway and check for water in the recess beneath it.

 

[rup5555555]

just changed the FPC and it didn't help. do i need to reset anything after installing the new one?

a fair amount of sand in the hole but no water....

 

[Pukmeister]

just changed the FPC and it didn't help. Do I need to reset anything after installing the new one?

a fair amount of sand in the hole but no water....

They are just plug & play Rupert, I'm a bit gutted that didn't sort it, I'm really out of ideas now.

Top tip: smear the FPC sealing ring with vaseline or similar to prevent possible future water ingress.

I think you really need a diagnostic test now from a GS911 (or BWM GT1) to tell whats wrong. Failing that, if you have an R1200GS riding buddy nearby, you could try swapping components from bike to bike one-at-a-time eg stick coils until the fault clears, then you'll know which replacement item to buy.

You could also check the continuity of the stick coils internal wiring with a multimeter set to resistance. Primary windings are low, roughly 0.87 Ohms across terminals 1 and 3. Secondary windings are high, roughly 6 KiloOhms across terminal 2 and the spark plug connector inside the coil.

Have you checked all the wiring connectors to the stick coils and fuel injectors for dirty, corroded and loose connections ?

 

[Pukmeister]

Another thought. Are the little rubber sealing caps in place on the test points of the throttle bodies (where you connect to do a cylinder balance). If one has perished or fallen off, one cylinder could be running very lean due to air bypassing the throttle body giving rough running. Unlikely I know, but easy to eliminate.

Is the air intake snorkel and air filter free of obstructions eg blocked with leaves or debris (I am now clutching at straws).

 

[rup5555555]

i think you're right Adam, i need to get this to a dealer - i'm booked at south london a week today, i'll just have to use my trusty bicycle until then...

the sealing caps are all in place, i'll check the intake later today, but i'll wait to check the coils at the dealer

thanks for all the help - i'll update the thread when the answer is found

Rupert

 

[Pukmeister]

Fair dos Rupert.

FWIW I just checked my bikes stick coils rather than trust the manual, my primaries were 1 Ohm and secondaries all measured 4.5 KOhms on my old cheapo analogue multimeter.

The lower Left hand secondary stick coil is badly rusted externally, also swollen and cracked through at the large end due to internal corrosion of the ferrous core inside.

They are polarity sensitive on the secondaries, must have a diode fitted inside so gotta have +ve on pin 2 and -ve on the spark plug terminal to see a reading on the meter. Oddly I got no reading at all with a digital multimeter.

Just ordered a new stick coil at £69 (Ouch), the rusted one tests fine electrically but I bet it is the reason why I sometimes feel what I'd describe as coarse running (rather than silky smooth) if it is breaking down under load or when wet. Either way it is only a matter of time before it dies so you have done me a favour.

 

[rup5555555]

Just checked the resistance of the primary coils - one 0.9ohms but the another moves around 3 to 4 ohms then after a few minutes settles down to about 1.5 ohms - is it faulty? Is this the problem?

Anyway, booked into South London on Friday - should I ride it, will riding damage the engine?

 

[Pukmeister]

It's a possibility if the resistance changes. Could be your multimeter or the connection of the test lead to the coil though giving a higher than expected resistance.


If you don't have access to a similar bike to swap parts and see if its fixed, its probably best left to the dealers.

I'd play it safe and get it recovered if they can collect due to risk of detonation causing damage or unburnt fuel washing down the cylinder bores and diluting the oil.

 

[rup5555555]

South London checked it out and said there was zero compression on the right.... was very suprised at zero - me and a mate will be stripping it down tomorrow to have a look, I hope for the best