Fluxuating idle, stalling, low rpm surging

[Jcornwell101]

I purchased a 2014 trophy with 21,000 miles on it. Service history was unknown so I took it to a reputable shop that the Triumph dealer near me sends their bikes to for the 20k service. Before going to them the trophy didn't have any issues. But, coming back it has a fluxuating low idle and will stall at times till it warms up. Once warmes up idle will drop to 700-800 rpm then goto 1100 rpm and back to 1000. It will keep doing this cycle. Plus the bike bogs and surges alittle bit in the lower rpm range until about 5k rpm.

Under comfort the issue with the idle just means giving it alittle more gas and their is a bog then it accelerates like normal.

In normal or sport mode the throttle has a bog and you can feel it surging like gummed up carbs. The bike is throwing no codes either.

I took it back to the shop saying I don't feel safe to ride it. They replaced the throttle bodies, sent the injectors out to be cleaned, and replaced/ reset the throttle position sensor. It's still doing the same thing but not nearly as bad.

I have been a lurker here for awhile and saw a thread about tsbs and software updates regarding tps issues and stalling. Have any of you had this issue before? Has anyone had a software update or recall for a similar issue?

The shop told me to keep running injector cleaner and it will clear up on its own. But I don't think it's a gum up or bad gas issue, I think it's an electrical issue.

[digital]

  to the forum.

It appears that the throttle sensor adjustment or throttle body adjustment is not properly adjusted.

As always, I advise that when adjusting the throttle bodies. The accelerator sensor is also checked, since when making one adjustment or another, either of the two adjustments can vary.

The software issue could improve. If the corresponding software is placed on it. There are several different software for Countries, if I remember correctly, such as: France, Japan, etc. It will also depend on the type of Exhaust that your motorcycle has.

[Coconut]

A couple of things :

"In normal or sport mode the throttle has a bog and you can feel it surging like gummed up carbs."
Those Modes ( and the other one - "Comfort" Mode ) have NO effect on the engine performance,
they only adjust the Electronic Suspension settings !

"The shop told me to keep running injector cleaner and it will clear up on its own."
... and that's a "reputable shop" ? 

I would bet good money that this suggestion won't work,
and if the fault wasn't there before they had the Bike for the costly 20,000 mile service,
then it is surely their responsibility to put right whatever has gone wrong !

It could be something as simple as an Air Leak at the Throttle Body transition pieces,
which can be awkward to refit and seal correctly, so I would double check that.

If they really did replace the Throttle Bodies and Throttle Position Sensor,
then that will have been EXPENSIVE, and because the same problem is still present,
albeit you say to a slightly lesser extent, it may have been unnecessary !

A reputable Triumph Dealer will have Diagnostics equipment and the information needed to diagnose
various sensors and settings, and identify if any of them are causing this issue, if it isn't a simple air leak.
For example if the Engine Temperature sensor was faulty, it could be commanding the ECU
to run the engine richer and at higher Rev's, even when the engine is not cold.

I have also heard of a similar ( not identical ) problem, that was due to burnt out valve(s) !
The major part of the 20,000 Mile service is to adjust the Valve clearances !   

Have a read of this Topic : DealerTool Data

Let us know when they find out what's wrong !

[Jcornwell101]

Coconut, I agree with much of what you said and have gone round and round with them. I am in the same spot where I either want to do it myself or take it into a triumph dealer.

I have a heavy automotive electrical background snd with the software, meter, and piercing probes I'm sure I can fix that. But, as for the burnt valves that is a good possibility.

The shop showed me carbon build up, corosion and pitting on the valves.

As for the suspension modes I didn't know that, I literally just bought the bike. Because, I wanted a tourer and was impressed with my dad's rocket.

I thought that it changed settings in the traction control and all of that as Indepedant drive modes so I apologize.

[Coconut]

No apology needed - that's a common assumption !

Whoever did the 20,000 Miles service, if they are used by a genuine Triumph dealership
to carry out those Services, they must have the Triumph Diagnostics equipment, mustn't they ?

... or at the very least an After market version such as DealerTool or TigerTool ?

As you will see in that other Post I linked to, for the Burnt valves,
it was only after a lot of head scratching that the owner managed to get the bike to run
long enough to reach operating temperature, and use his DealerTool software to see the
wildly different readings for Ignition Advance etc. between the cylinders.

If there was carbon build up, corrosion and pitting of the valves,
was anything done about that ? - It seems a bit of a false economy
while it was all stripped down not to have addressed those issues,
which could well be the cause of your rough idling problem. 

If the workshop that did the Service won't help any further,
and the original Triumph Dealer that referred them seeming to not
want to do this kind of work, your best option might be to find another
Triumph Dealer that IS reputable, and preferably recommended by others,
put your trust in them, and try for a contribution to the additional costs
from the original workshop owners, once the fault has been identified and put right.

If you add your location ( I can only see that you are in the USA )
then other Members may be able to make some recommendations on who to use.

Cheers 

[Coconut]

Another thought / question for the workshop that carried out the work ....

"The shop showed me carbon build up, corrosion and pitting on the valves."

Presumably then, they removed the cylinder head to access the Valves
to have been able to show you that carbon build up, corrosion and pitting ?

If they did remove the Cylinder Head - Why did they do that ?

It's not called for during the 20,000 mile service, it is not necessary to do so
to adjust the Valve clearances, and according to the Service Manual if the
Cylinder Head is removed, the Piston Liners should also be removed and re-sealed ! ?

[STJIM]

I think you are having a similar problem that I had when I did my 20K mile check.  I had a leak at one of the rubber connectors between one of the throttle bodies and intake manifold connectors.

What happened was after I loosened the clamp for each of the rubber connector on the throttle bodies, one clamp it fell out of position in the groove it normally sits in in the rubber connector and when I tightened it, it didn't actually make a good seal since it wasn't in the groove when I tightened it - me bad !!

It's easy to check for a leak.   While the bike is running, place your palm over a T.B. intake.  You should feel a fairly good suction and the bike will stall if you don't remove your palm quick enough.  Do this for all 3 T.B.'s.

At the T.B. with the leaky connector, I could hold my palm over the T.B. opening and I couldn't feel any suction and the engine kept running.

[STJIM]

Originally Posted by Coconut

Another thought / question for the workshop that carried out the work ....

"The shop showed me carbon build up, corrosion and pitting on the valves."

Presumably then, they removed the cylinder head to access the Valves
to have been able to show you that carbon build up, corrosion and pitting ?

If they did remove the Cylinder Head - Why did they do that ?

SNIP ......

Maybe they were talking only about the intake valve stems  - you can see them through the T.B.'s with the throttle plates open ?

But what difference would that make since the bike didn't have this problem before it was brought in for service ??