Help.. Synchronizing of the Throttle Bodies Disaster

mpgscott

mpgscott

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Been servicing the GS the last day or so, 35k miles and its a 2011.

Noticed that the cable was tight after watching the old mechanic video, so took some slack back.

I have a 4 bank carbtune meter two blocked off with my caps off the TB and a GS911, i have got the bike upto temp and i just cant get it too idle worth a hoot since taking the slack off at the throttle. So its like the bike had been set to hold idle with the throttle adjustment at the bars.

I have gone through all the steps and no matter what i try i just cant get it to tick over. I can get them adjusted and balanced holding 3k revs but as soon as i complete the test with the GS911 and put the rubber blanks back on the TB when i start it just wont hold idle unless i hold the throttle open slightly. Thought i had it a few times, but no. I have even tried back to scratch with the cable adjusters but just no joy. So if there is any videos or instructions to start from scratch that be great. Assume best option is to try and get it idling fine with nothing connected. I have gone through the idle calibration and it all passes fine on GS911. All the steps seem to follow. The last time i tried there as i hit the ok after completing the bike started climbing to like 4k revs so god knows whats going on with it..

This weeks been a disaster, just at the end it wont turn over so not sure if my new last year battery is goosed or if the starter has had enough. God wish i hadnt started it.

Anyone else had similar and can give me some advice?

Much appreciated any thoughts.

Thanks
MarkIMG_8525.jpeg
 
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Could the TPS be out? Wife's Guzzi wouldn't idle and kept cutting out, plugged it in and it was only a bit out so set it to what it should have been and voila.

Not sure how to do it on a GS as haven't had to do it yet!!

Edit: Had a quick Google and you cant adjust the tps on these, apparently they calibrate every time you switch the ignition on. Lots of warnings about not having your throttle open when switching the ignition on.
 
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No matter what I try I just can’t get it to idle.

I did check for any errors and the stepper motor I have disconnected, the one saying ‘Throttle Position potentiometer faulty’ could this be a cause?

Also the other ‘Injector vaive 2’

I cleared both and tried a calibration again. I can get the TB to sync at 3k but it just will not idle unless I use the throttle handle adjuster to hold idle or it just dies.

Sounds ok but just no idle.

This is a video showing what’s happening after repeated calibrations including idle motors. Tried with no tension on the throttle cable but it just won’t idle.


Good news is the battery was just flat from repeated starts, left it half an hour and it’s fine starts up.

IMG_8539.jpeg
These two faults have not re-appeared after doing the TB balance so not sure if they were simply old ones?

Thanks in advance for any thoughts or guidance.
 
you are not meant to touch the throttle body end stop screws they are fixed at manu and you NEVER adjust them
do not set carb balance at idle - do it with throttle cables holding the butterflies open on a hot engine circa 2500 - 3000 rpm with a fan on the oil cooler
do the valve clearances and clean the throttle bodies first

exhaust servo motor is a waste of space
TPS, did you knock the wires off - they are calling it a throttle position potentiometer
injector valve - do they mean a fuel injector - if so why not call it by its logical name ?
you do not disconnect the idle stepper motors - theses days you can lock them out using diagnostic tool - I've never had an issue with them fighting you as you do it at higher revs... as that's where you ride round town and where you want it to run correctly - idle is a recalcitrant wandering mess regardless

if you have fiddled with the end stop screws have you now got them closed too much - if so likely you'll never get them back to std - I guess they are bench flow tested then locked - the stepper motors make up the difference to match what the ECU is telling the bike to run at - have you re done idle stepper motor calibration - so they at least know where fully open / fully closed is ?
 
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botus said:
you are not meant to touch the throttle body end stop screws they are fixed at manu and you NEVER adjust them
do not set carb balance at idle - do it with throttle cables holding the butterflies open on a hot engine circa 2500 - 3000 rpm with a fan on the oil cooler
do the valve clearances and clean the throttle bodies first

exhaust servo motor is a waste of space
TPS, did you knock the wires off - they are calling it a throttle position potentiometer
injector valve - do they mean a fuel injector - if so why not call it by its logical name ?
you do no disconnect the idle stepper motors - theses days you can lock them out using diagnostic tool - I've never had an issue with them fighting you as you do it at higher revs... as that's where you ride round town and where you want it to run correctly - idle is a recalcitrant wandering mess regardless
Click to expand...
I’m not sure you bothered to read the original post before jumping in ……
 
botus said:
you are not meant to touch the throttle body end stop screws they are fixed at manu and you NEVER adjust them
do not set carb balance at idle - do it with throttle cables holding the butterflies open on a hot engine circa 2500 - 3000 rpm with a fan on the oil cooler
do the valve clearances and clean the throttle bodies first

exhaust servo motor is a waste of space
TPS, did you knock the wires off - they are calling it a throttle position potentiometer
injector valve - do they mean a fuel injector - if so why not call it by its logical name ?
you do not disconnect the idle stepper motors - theses days you can lock them out using diagnostic tool - I've never had an issue with them fighting you as you do it at higher revs... as that's where you ride round town and where you want it to run correctly - idle is a recalcitrant wandering mess regardless

if you have fiddled with the end stop screws have you now got them closed too much - if so likely you'll never get them back to std - I guess they are bench flow tested then locked - the stepper motors make up the difference to match what the ECU is telling the bike to run at - have you re done idle stepper motor calibration - so they at least know where fully open / fully closed is ?
Click to expand...
I’ve not touched the screws but I will make sure they have never been tampered with for sure, I’ll check see they are still aligned with the paint markings.

I’ll clean the throttle bodies for sure as well. 👍

I’ve not set the balance at idle I’ve held revs at 3-4k and balances fine. Used the GS911 to run through but didn’t do adaptions so I’ll try that tomorrow.

However I have messed around with the adjusters on the a fair bit so I need to get it back to normal. Was just watching a video where they use the same Carrie unit and so I’ll see I can match mine the same.

My issue is it just won’t idle, balances up correctly.
 
botus said:
injector valve ..... whatever that is might well be your idle issue
Click to expand...
Sorry, you asked earlier about if I disconnected the TPS and I did when I was checking connections were made correctly. So that might be why the TP potentiometer was showing as faulty. The bike wasn’t running when I’d the make break but maybe it logged the fault and the valve is also linked possibly.

I’ll do more investigating tomorrow.

If anyone has a carbtune what values you get when balanced at 3k by chance? Video I’ve seen shows 32cmHg but be good to confirm.

Lastly what temp can we allow the bike to get too? I’ve a fan blowing on oil cooler as well but keep being cautious not to run for too long.

Thanks for all the reply’s as always..
 
Number one Disregard that fool BUTTASS up above !!

Number 2 Do not panic !!! Start the diagnostic process from the beginning

I remember my Old foreman at BM hating these things with a passion

Anyhooo!!

A) Sort the battery Either charge it or Replace but a decent Workshop autoparts store can test them for you )

B) get the bike to full operating temp

C) Disconnect Stepper motors with Ignition off

D) Get someone with you to hold the throttle at about 2000 rpm whilst you adjust cables to set the balance (3000 if you wish to replicate the video)

E) Switch off, reconnect Stepper motors, Ign on Cycle it a couple of times (Just cos it makes you feel better :D )

In theory it should start and run as it used to

If all you did was twiddle cables ???

Then some cable twiddling is all it should take to get it sorted (Plus Battery / Starter)

In the words of Private Jones

Don't Panic!!! Don't Panic!!
 
DrFarkoff said:
Number one Disregard that fool BUTTASS up above !!

Number 2 Do not panic !!! Start the diagnostic process from the beginning

I remember my Old foreman at BM hating these things with a passion

Anyhooo!!

A) Sort the battery Either charge it or Replace but a decent Workshop autoparts store can test them for you )

B) get the bike to full operating temp

C) Disconnect Stepper motors with Ignition off

D) Get someone with you to hold the throttle at about 2000 rpm whilst you adjust cables to set the balance (3000 if you wish to replicate the video)

E) Switch off, reconnect Stepper motors, Ign on Cycle it a couple of times (Just cos it makes you feel better :D )

In theory it should start and run as it used to

If all you did was twiddle cables ???

Then some cable twiddling is all it should take to get it sorted (Plus Battery / Starter)

In the words of Private Jones

Don't Panic!!! Don't Panic!!
Click to expand...
Thanks, my only concern is that there was no slack in the handle bar throttle cable it was as if it was set to hold idle and I’d never noticed until I watched a video stating that there should be a few mm of travel when you pull the throttle before it takes tension.

With your suggestion I simply switch on ignition to zero steppers motors, switch off. Then simply unplug the stepper motors and as long as bikes at temp I can tweak cables to get the balance correct. So holding 2k is enough to do this then happy days that will give a little longer to avoid getting too hot. Afraid no pals so on my own, just bikes kept miles away and no internet 🤦‍♂️

I’m going to go give it a try again this morning but my concern is that somethings up with the idle circuit.

My thoughts were also, reset the adaptions.

Pull battery off to reset ecu and then do the ignition on and three full sweeps of throttle.

If this doesn’t work then clean ICV on both sides and if this fails then get another TPS ordered even second hand to try.

The joys..
 
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Check that both idle control valves are actually operating, if one is not then it can give the symptoms you describe. If the retaining tab on the plug to the valve is broken it can look as though the plug is inserted but is not making electrical contact. I can't remember if this gives a fault code however.
 
I tried again first thing cold and with slack on throttle just not idling.

So I reset adaptions and it was slightly better. However I then tried the little tweak on the TPS and didn’t make a difference unfortunately.

I then took apart and cleaned up both ICV and checked they worked which they did.

I also took out the injectors out and gave a clean.

Then tried again, I simply unplugged the stopper motors and took it to 2k and balanced the TB.

After I got the TB balanced and disconnected everything it all looks to be good.

Have a look but all seems fine to me.

Happy days and thanks for the pointers.

Balanced view of carbtune

Everything disconnected and back to as it should be. Idle is fine and smooth through revs.


Started it a few times and seems fine. I now need to get it out a spin but my access is blocked by a big boat.

Oh well need to wait a few weeks.

Bloody throttle heated grip is buggered. Aaargh Motorworks will be to the rescue.

Thanks everyone for the help..
 
I also tested the coil packs and I’ve one of those failed. Can’t believe it runs so well even only on one coil it’s crazy. So I’ll get a new pair of uppers as I’m sure the other won’t be long in failing.

Expensive, £460 for two and a heated grip genuine..
 
mpgscott said:
I also tested the coil packs and I’ve one of those failed. Can’t believe it runs so well even only on one coil it’s crazy. So I’ll get a new pair of uppers as I’m sure the other won’t be long in failing.

Expensive, £460 for two and a heated grip genuine..
Click to expand...
Beru
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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