KrZy8 Hissy Fit - Stumbling/Dying off Idle,

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I am no fart smeller but -

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

I vote for this as the next step.

Good luck with your search

-Steve
Thanks for the reply -Steve :)  My DL650 did the same thing when it shat it's fuel pump.. 

 
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.
You know, you're right. Hadn't really thought about that before, but yep. Unless it's an oil burner, those plugs are going to look good. Unless they are wet with gas from no spark maybe. 

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...
Dean Tanji had a frustrating issue while riding his DL overseas..  Bucking/Stalling then fine then back to hissy fit city. After all was said and done, a bad fuel pp.

Thanks for the input! :)

 
! THANKS TO EVERYONE !

2020-11-27 - Rough Running Fixed

For I have met the enemy, and he is I.

Some worthless .02 cent tech forgot to fully snap this connector together.
Was preparing to remove injectors then test fire, with tank connected, via Diagnostic Screen.

Went to wiggle injector #1 connector, and the big gray connector came apart. 

SIGH. 

"It's really hard to be perfect." (Steve Burket)


Here's what she sounded like when sick.

2020-11-27 RoughRunningFIXED from dcarver220b on Vimeo.

 
Good news DC...glad the 'ol gurl is running again! How long since the "tech" was under the tank?

~G
Under 5th Amendment... Oh about 3 or days ago. Replaced injectors with refurb and the saga began.

Working outside, under minimum lighting, I missed to fully connect connector.

So my bad, Live and Learn!

I did lean the CO from 90 to 20, based unscientifically from 'response' to idle to throttle application and idle RPM.

Riding her tomorrow, so results in soon!

 
Well CRAPOLA.

The ride today went from running good to bad to great to barely starting, huge stumble off idle, 23 mpg to 41 mpg.

I still haven't found the root cause problem.

 
Did you try unplugging the O2 sensor?

Also, check hoses to MAP sensor to make sure there isn't crud in them.

Check for vacuum leaks?

Have you checked fuel pressure on the rail?

Have a look at the inlet screens on the fuel injectors - just in case. (I know you changed them)

(Grasping at straws here...)

 
Did you try unplugging the O2 sensor?

Also, check hoses to MAP sensor to make sure there isn't crud in them.

Check for vacuum leaks?

Have you checked fuel pressure on the rail?

Have a look at the inlet screens on the fuel injectors - just in case. (I know you changed them)

(Grasping at straws here...)
Thanks Ross, I appreciate your help. Sincerely.

After the CBX leaves the lift (tomorrow afternoon) KrZy8 goes back up. 

I reviewed my CandyButt website.. and looking over time.. .I've had this issue over and over.. 

https://candybuttorg.ipage.com/cba/comment/852#comment-852

..and it all started after my JB Weld Fix in the Aux Tank 'back in the day'... 

I see a clean FI system on eBay https://www.ebay.com/itm/2006-Yamaha-Fjr1300a-Abs-Main-Fuel-Injectors-Throttle-Bodies-3p6-13750-01-00/173903204612?epid=23016575565&hash=item287d705104:g:W6gAAOSwbdxc2xpj for reasonable price...

Just might try it.. 

 
Fuel rail, injectors and throttle bodies.  Great deal. 

I remember your issue due to epoxy in the aux tank degraded by gasoline. Are the inlet baskets of the current injectors looking dirty?  This could explain poor performance but what about intermittent poor running?  Any evidence of crud looking at the fuel pump inlet screen or the bottom of the tank? 

 
So I've been busy 'sorting' the Cbx and Kz1300. Sigh. 

Gonna send the ECU to Ivan for a re-flash. Discount if shipped back before Dec 28th.. so will work in parallel paths. 

But this has happened..

2020-12-05 New to Me Fuel Injector Arrives

Supposedly from a 17k mile 2006 FJR..

x  

The throttle plate 'grunge' factor looks about right for 17k miles.


x  

x  

x  

x  

x  

x  

Will install and see if it takes care of the stumbling and erractic running, from perfect to phooked...

Also ordered a new to me FI wiring harness and airbox sensor...

 
Make sure fuel system is CLEAN!  If residual junk from the epoxy in your aux tank FUBARed the last set, you don't want it to happen again.
As far as I can tell, it's ***** and span clean. I ran a bore scope into both tanks and didn't see anything unusual. 

And... the problem comes and goes instantaneously, not a gradual degradation. It's binary.. Runs great or ******, BAM!

The new to me fuel FI rail also provides a different pressure regulator and sensor. (what is that, ambient air pressure?) 

Also bought a new to me FI wiring harness and air box sensor.

Will be working it tomorrow. Right now, the water heater sprung a leak

 
First of all, I hope this fixes it.  Second, I hope you find out which of the various parts you changed out was the root cause.

The on-off nature of the poor running makes me think electrical like a bad connection or a coil breaking down when wet or hot.  Could also be some sort of sensor that provides flaky readings some of the time or under some conditions.  MAP sensor, O2 sensor etc.

 
First of all, I hope this fixes it.  Second, I hope you find out which of the various parts you changed out was the root cause.

The on-off nature of the poor running makes me think electrical like a bad connection or a coil breaking down when wet or hot.  Could also be some sort of sensor that provides flaky readings some of the time or under some conditions.  MAP sensor, O2 sensor etc.
I'm thinking sensor failure with heat soak. Coils are new to me from eBay. Another thought might be spark pulse pickup coils.

 
I'm going to go with a dirty or bad MAF.  I had same symptoms on a Toyota.  I sprayed some carb cleaner in the MAF (it was removed for the cleaning) and it ran fine after I reinstalled it.

 
I'm going to go with a dirty or bad MAF.  I had same symptoms on a Toyota.  I sprayed some carb cleaner in the MAF (it was removed for the cleaning) and it ran fine after I reinstalled it.
I have a new MAP.. if we're talking the same item... monitors air box ambient pressure?

 
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