KrZy8 Hissy Fit - Stumbling/Dying off Idle,

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dcarver

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Looking for Help

Well, here we go again. KrZy8 throwing a hissy fit.

Running rough / stalling off idle. 32-35 mpg not high 30's low 40's as baseline. Unfortunately, KrZy8 sat for too long while I was away working.. ~ 3 months total.

Troubleshooting Plan

  1. Check Compression


    COLD 1=190 2=190 3=175 4=175 7.9% delta. Note.. I used a throttle lock.. and think it slipped at #3, 4 reading, closing the butterflys somewhat. Will test later.

[*]Check Air Filter for mice nest

  1. Clean. Air filter kinda dirty but not excessively bad. Replaced.

[*]Check/Replace injectors

  1. Had 4 refurbished RC Engineering from 2017 sitting in the spares box. Tested each using 9 vDc battery. 3 of 4 not clicking. Used a home made test fixture to supply gasoline under slight pressure to injector, whacked them with screw driver, and each then clicked and sprayed like a male cat.

[*]Replace fuel in tank with fresh

  1. Thinking some condensation might have formed.. and  I use SeaFoam, which FortNine recently demonstated is not the best storage solution.

On the lift, KrZy8 is crisp, GREAT. Fast throttle response.. Snappy!

So that's it for now. Now let's go ride..

--------------

Good news, bad news 

Good news - Ran great for first 50 miles or so.. Snappy, high 30's mpg, STRONG

Bad news - Instantly... KaBoom, dropped a cylinder or so it seems. Exhaust rough, has the hollow sound of a cylinder not firing. WTFO? Decided to take 'main' roads home for easier tow truck access should it come to that.

MPG's now in low 30's high 20's.

Idles fine. But under load, missing, and very noticeably.

Then, MAGIC and instantly, running purrfect and MPG's climb to mid 40's. Oh Happy Day.

Then, BAM, and back to crapola.

What can it be?

  • Sticky fuel injector?
  • Water blob in tank, sloshing around, getting picked up once in awhile when cornering or whatever?
  • Ignition coils? (Idle is fine, throttle under no load fine, but under load missing... higher compression blowing spark out?) BTW, coils, leads, caps replaced with used eBay units 2019-08-10.
  • Spark plug going south?
  • Fuel pp failing (I can put the 2013 tank of the 2006 to test!)
Unfortunately, no auto store in Paso Robles or Atascadero has qty 4 CR8EIX NGK plugs.. Decide to soilder on to Paso, pick up 3 NGK's then to Atascadero for some fancy smancy E3 plug.. just for testing.

Current plan

  • Replace sparking plugs
  • Check battery connections + ground (even though starting and charging is working fine)
  • Pull and test FI's on bench with 9vdc battery and test rig
  • Re-run compression check when warm and known TB's fully open
Truly dissapointing but so it goes.

HOPEFULLY I'll find something really stupid I did.. like not fully connecting a FI connector or likewise..

Turkey day tomorrow.. but maybe I can get to the shop and play. KrZy8 already on the lift. 

What do the Fart Smellers think?

 
Assume no error codes?  

Maybe coils but haven't actually seen failed coils on FJR.  Same with plugs - unlikely but easy to check.  Wires to sparkplug boots?  No crap in gas tank or fuel pump pickup screen?  Inlet filters of injectors clean?  Try fresh fuel.

Any recent maintenance?

Any chance of fuel tank vent plugged? Whoosh sound when tank is opened?  Are you using aux tank?

Kinked fuel hose?

See how it runs with O2 sensor disconnected.  Assume no Power Commander?  If so, take it out of the circuit. 

Good luck!  

 
I've experienced Spark plug going south on my '06. Symptoms the same. "Seems to run OK till under load then .......

NBB

 
Checked Error Codes... 1 instance of #12 "No normal signals received from the crankshaft position sensor."

Cleared it, started and ran several times, no re-occurrence, don't think this is the issue..  as symptoms remain and w/o CS position signal, no run.. would be my guess.

 
SparkplugCapOlogy

All connections wire to boot tight.

Resistance across resistor kOhms
1 - 10.66
2 - 9.58
3 - 9.23
4 - 10.11

Resistance value *through boot* e.g. resistor installed
1 - 10.66
2 - 9.62
3 - N/A forgot to measure
4 - 10.11

Cleaned all resistors/ brass conductors

Trimmed plug wire back 1 mm, reinstall caps All wires looked clean, no corrosion, and As Found condition was tight.

 
Checked coil performance by sparking plugs via diagnostic mode. 1 & 4 Sat, 2 &3 Sat. Used old plugs for test, new plugs already installed.

Put tank back on and fired her up.

Running r o u g h.  Much worse. 

Might this be a fueling issue? Had siphoned off the tank to 1 bar indicated on fuel gauge, removed, then reinstalled for this test. Might there be debris or water at tank bottom causing issues? She ran much better before this latest evolution of checking wires and caps, resistors.

BTW, same 'hollow' sound. 

Thinks that make you go hmmmm.

 
OK. My bad. Gas tank too empty for test fire described above. 

Tried to drain all fuel from main tank using aux tank feed bung.. and nothing come out. Hmm. 
Turn tank upside down, try to 'slosh' gas to RHS where aux bung is and still no fuel coming out.

Can hear *some* fuel in that however.. 

Anyway, fired up and she's back to purring. 

Of course, she was purring like a big kitten right before instantly having a miss so who knows.

Me thinks I'll get to coil location anyway and look things over later.

Edit. Ran rpm up slowly to 7k, lots of sputtering and popping along the way. ~6.5k rpm large rpm fluctuations. Upon return to idle, idle is very low, ~700-800 where I normally have it 1.5k (I like high idles in my engines).

Hmmmmm

 
Assume no error codes?  

1 error code - crank position indicator

Maybe coils but haven't actually seen failed coils on FJR.  Same with plugs - unlikely but easy to check.  Wires to sparkplug boots? 
All good.

No crap in gas tank or fuel pump pickup screen? 
Charging the internal camera now! I only run top tier fuel, but anything is possible.

Inlet filters of injectors clean?  Try fresh fuel.
Replaced existing injectors with refurbs from RC Engineering and it ran great for about 50 miles.. 

Any recent maintenance?
Nothing major..

Any chance of fuel tank vent plugged? Whoosh sound when tank is opened?  Are you using aux tank?
No whoosh sound.. Using Aux tank, yes, electric pp to replenish main tank.

Kinked fuel hose?
No.

See how it runs with O2 sensor disconnected.  Assume no Power Commander?  If so, take it out of the circuit. 
Good idea will that too. No power commander.

Good luck!  
Thanks Ross, Appreciate you.



 
Pics

2020-11-26 Pictures

RC Fuel Injection data sheet for injectors installed a couple of days ago. 2017.


Please install immediately the box says. Reason being is the injectors get sticky without gasoline lubrication.
3 of 4 were sticky.. But see below.


Un-Stuck them by appling gasoline via syringe and activate injector via 9 vDc battery. A good whack with a screwdriver helped too.


Old injectors.


New injectors. (refurb)


After installing new CR8EIX NGK plugs and testing spark on old plugs via Diagnostic screen.
Boots lubed with hi-heat silicone to facilitate removal next time.


On the lift again... Gotta get 250k outta her..


Resistor and plug.


Cyl 2


Cyl 3


As-Found wire after cap removal.


1 mm trimmed, ready for cap install.


More resistor/plug pics.




Local shops didn't 4 CR8EIX so one is a stupid E3 plug.


Plug comparison.


Good stuff.


 
Idles fine. But under load, missing, and very noticeably.

Then, MAGIC and instantly, running purrfect and MPG's climb to mid 40's. Oh Happy Day.

Then, BAM, and back to crapola.
I am no fart smeller but -

These are the same symptoms I saw a yr ago when my riding buddies fuel pump shit the bed.

Fuel pp failing (I can put the 2013 tank of the 2006 to test!)
I vote for this as the next step.

Good luck with your search

-Steve

 
Sparking plugs fuel air color mixture look purrrfect.
With modern EFI systems, "reading plug color" is mostly a thing of the past. Until things get really bad, the computer usually adapts and the plugs remain a "good" color long past the way it was in the past. So, bottom line is that you can read the plugs but often that doesn't tell the whole story anymore.

 
Hey Mr. Carver, just thought I'd stick my schnoz in here and offer a couple thoughts from a challenging situation I watched my buddy [rides a 2013 Suzy V-Strom 1000] go through throughout this past riding season. 

Back in June his Strom started sputtering under load while we were out in the wilds, and it became so bad, we decided to tell the other 2 guys to go ahead and ride home (700Km) without us; I had become freshly retired that week, and had lots of time to stay with my bud another day and help him however possible. 

We got permission from the motel manager, then after picking up a large drain pan, some paper towel, rubber gloves, tore his Strom down there in the sunny parking lot in front of the room we booked for another night. Tank was right full of fuel; as a foursome we thought we were all riding home that morning, but she sputtered and died a number of times trying to leave that mountain town. We extracted the fuel pump, tore it down completely, found no crud. Reassembled, checked over all the fuses, wiring bits we could think of. Still running like crap when he throttled up to a certain rev (~5K ?), - AND only under load. 

Broke for lunch, reviewed everything we could online, with some tips, but little helpful insights to these symptoms. We ended up having a guy from a distant bike shop come collect the Strom with a truck, and after paying him for about 2.5hrs of his time, were still no further ahead. Buddy and I decided to just push ahead anyway, with me riding sweep behind him for over 700kms to get home. She would run fine for a Km or two, then die (total engine shutdown) - then come back to life; rinse, repeat about 200 times...

Back in his home garage, we met up again, and went through the motions of removing and testing his fuel injectors, all good. He was quite frustrated, but after getting away from the problem for a few days, he returned, and decided to trace through the wiring (again) to both the sidestand saftey lock-out switch, and the clutch lever switch. 

Voila' - the sidestand switch was becoming flakey, so it was chattering open/closed/open - and as far as we could now surmize, this was most obvious under higher revs  / under load while physically riding. 

I do recall other contributors on this thread suggesting to check some of this ancilliary stuff, but don't know if you'd ruled this kind of thing out already?

Best of luck in your quest...

 
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