2014 Rough idle, sputtering and hesitant at low rpm...

[Biker]

Hi all.

My 2014 has been a little poorly for about a week now.

The issue is rough idle and hesitation up to about 3.5k rpm

It is less pronounced when cold and at it's worst when the engine is up to operating temps.

The tickover when warm sounds like it is mostly running on 3 cylinders.

Low rpm acceleration is poor and the bike hunts and is hesitant.

Once I hit 4k rpm everything smooths out again and the bike behaves normally.

This happens in all modes (inc slick).

Since there are 2 sets of injectors could it be that if one set governs low speed fuelling that the low speed injectors may be clogged?

After reading around the subject others have also had spark plugs wear prematurely so i'm gonig to rip it apart this weekend and change them (they were allegedly changed 8k miles ago by a dealer but since it is a pig to do they may have skipped it).

So far i've fed it some injector cleaner (Redex advanced) to see if that helps but no joy...

I'm just hoping it is not some sort of electrical gremlins causing ignition timing problems!

Anyway folks, anyone else had this issue?

If you did what was the diagnosis and how did you get it resolved?

 

[Oli]

It could be a faulty lambda sensor

 

[Biker]

Checked for faults with a gs-911, nothing found... if a lambda was faulty it should show up?

 

[Oli]

Checked for faults with a gs-911, nothing found... if a lambda was faulty it should show up?

Yes a lambda fault would should up on a GS-911. As it?s not the lambda sensor it?ll either be a fuel or spark issue as you say in your OP

 

[JamieMac]

Ockham's razor, the simplest answer is normally the correct answer. Spark or Fuel. Do you have a temp gun you could point at each down pipe to see which cylinder is not firing? or a pipet, so you can drop water onto each down pipe to see which one is cool? J

 

[JamieMac]

Also were you working on anything directly before the problem occurred?

 

[Biker]

Yes I have a temp gun... good idea!

Fuel has been changed twice since the problem started so we can probably eliminate that.

I was not working on anything when the problem first presented, the only thing that happened at roughly the same time was a parking light blew.

 

[alex]

It does sound a bit like something goes wrong on closed loop...

 

[r25sti]

i would replace plugs first. cheapest quickest things to start with.

 

[CJK]

My friend had a similar problem and I believe it was a leaking gasket which allowed oil into the spark plugs so the bike flat hesitate and flat very easy to stall

 

[stuartb]

My Lamda sensor had an very slight-intermittent fault and wasn't picked up...then it went full blown and needed replaced...your issue does sound like an air fuel problem so could very well be the sensor on the road out...

Sent from my SM-G975F using Tapatalk

 

[Biker]

My friend had a similar problem and I believe it was a leaking gasket which allowed oil into the spark plugs so the bike flat hesitate and flat very easy to stall

Oh crap....I really hope it is not a blown head gasket!

On the plus side she is not burning oil or losing coolant so that is a big fat *phew* from me :stung:

 

[Biker]

My Lamda sensor had an very slight-intermittent fault and wasn't picked up...then it went full blown and needed replaced...your issue does sound like an air fuel problem so could very well be the sensor on the road out...

Sent from my SM-G975F using Tapatalk

Yes I really hope it is a dodgy sensor and the behaviour certainly points towards this as the bike is rough as hell up to 4k rpm then fine again above that. Either way the plugs come out for inspection and temp gun on the headers later tonight so i'll know more in the next 24 hours hopefully...

Thanks for all the replies so far

 

[P0u1]

Anywhere near Bedford? I got two sensors in my garage as my full system makes them redundant.

 

[Biker]

Anywhere near Bedford? I got two sensors in my garage as my full system makes them redundant.

I'm in North West London so I could be up to you fairly quick :cool-new:

Thanks!

 

[Biker]

OK.

Started at 17:30 and had the plugs out an hour later.

All the plugs looked fine with a perfect brown tan colour and no electrode wear or fouling.

However when I pulled coil #2 I noticed the rubber around just where the coil connects to the plug was severely damaged and I strongly suspect this was causing shorting to the head.

New coil ordered and the dodgy coil put back with bodged up insulation for now which should be ok until the new one turns up.

I arrived at the workshop with a toasty bike and did not have time to wait for it to cool down for a cold temp gun test.

Anyway she's all back together now with new plugs and i'm heading out for a test ride shortly.... watch this space

 

[Biker]

Test run complete and she's running normally at low rpm again YAYY!

Prime suspect: coilpack on cylinder #2 with wrecked insulation... whoever changed the plugs last should have definitely flagged it up and got it changed...

Back to happy biking :motorcyclesmilieK:

 

[CJK]

I?m pleased that you got it sorted and was not a major problem

 

[JamieMac]

Well done, what a relief. J

 

[stuartb]

Surprised that never flagged up on the system either..

Sent from my SM-G975F using Tapatalk