2007 FJR1300A Intermittently Stalling at Idle or throttle release

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JamesK

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I hope you guys can point me in the right direction to look for this problem as I'm running out of ideas.

I have a 2007 FJR1300A with ~208k miles on the ODO. The engine is still strong and everything else works (has been maintained as needed).

I've read through the various "Intermittently Stalling" threads but the issues listed don't exactly apply to me.

This problem seems to have started suddenly and only recently, no work has been done on the bike in the recent past/before this problem manifested itself.

The stalling happens at what seems totally intermittent times, not related to cold or hot engine state, throttle blips, etc. The one somewhat constant is that the bike is harder to start after the slow stall, almost feels like it's flooded as WOTL seems to have the best effect at restarting. The problem as I mentioned is that I can't seem to find any particular factor which leads to the stalling, sometimes the bike idles normally and other times it will either stall quite quickly or slowly drop RPM until it stalls (only takes maybe 30 seconds or less). The harder starts are after the slow stalling vs. the immediate stall. I have tried increasing the Idle RPM to 1,500 (current setting) but that does not make any difference other than possibly add a few seconds before the "slow stall" condition.

DIAG Checks:

- There are no Fault Codes displayed - d61:00

- The injectors each work (click 4 times) as described in the FSM diag tests.

- The fuel pump relay clicks 4 times as well and can be heard running if the Run/Stop switch is in the Run position. The one thing that does not match the FSM is he fuel system voltage. The diag shows 11V, while the Datel indicates 12.5V. Also the fuel pump initializes normally when the ignition is first turned on.

- The TPS diag d01: 17-100 range of motion per FSM.

- The rest of the Diag tests all pass according to the FSM.

The battery is always (including now) on a Battery Tender and is a Gel battery only about 1 year old.

As part of this problem, when the bike would stall if throttle is released it feels like it's not running on all cylinders, in the way the engine feels and sounds. However, this again is intermittent, so at other times the engine sounds normal and has full power.

The engine is not burning oil (any more than ever), the inside of the exhaust only has a very light black coating if you run your finger over it, as is expected with my current fueling configuration. Gas mileage is normal (unchanged from before). Using Regular or Premium gas makes no difference to this problem. I have run though many full tanks of gas purchased at different gas stations/companies and have run Seafoam in the tank. I have done multi-hundred mile highway runs siting on 80+ MPH to "flush" the system, etc.

I've already checked and cleaned (with brake cleaner and compressed air) all the Injector, ECU, TPS, PCIII, fuel pump, etc. connectors - no corrosion or grease was found on any of these and all seem to be making good contact.

Below is a list of related mods/farkles:

- Barbarian Mod - with CO bumped up by 5 over stock settings

- PCIIUSB, running the modified Wally Smoothness Map and O2 Sensor reconnected (ala HaulinAsh write up)

- Blueflame EVOIII slipons

- UNI Air Filter - cleaned and re-oiled 6k miles ago

- Airbox Opened up at the RHS side (to match the snorkel whole opening and snorkel cover removed)

- PAIR System removed and blocked off with the Wynpro plates

- New TPS unit - new part number for the 2009 model - about 15k miles ago

- New Air Temp Sensor (the one in the airbox) - about 15k miles ago

- Used very low mileage Coils and Leads

- Fuel Injectors Inspected and cleaned in with gas

- Injector cleaner and Seafoam run through a few tanks of gas

- Idle set at 1,200 rpm

- New NGK Iridium Plugs - 600 miles ago. The old plugs (with around 18k miles on them looked good, and I am sure where fine).

- DIAG tests performed per FSM - for fuel pump, each injector, spark, etc.

- TBS done 15k miles ago - virtually no adjustment was needed

- Throttle cable replaced at 180k and confirmed recently to be working smoothly

- Butterfly valves checked and cleaned at 170k

- All linkages inspected and re-lubed recently

This is was the bike on the Dyno at a little over 200k (done in mid June), engine running strong and putting down good power, at least for the mileage on her.



 
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James,

Not enough info given to assist us in your diagnosis.

Please reply with pertinent, concise, and accurate current conditions. :rofl:

Oh, the problem?

It's your ground wire.

(it's *always* the ground wire)

Sorry,

d

 
That's a real head scratcher. I've got nothing. You seemed to have covered everthing I would have thought to do. Will be interested to see what you come up with.

 
James,
Not enough info given to assist us in your diagnosis.

Please reply with pertinent, concise, and accurate current conditions.
rofl.gif


Oh, the problem?

It's your ground wire.

(it's *always* the ground wire)

Sorry,

d
Well, actually Don, thanks for reminding me, I meant to try by passing the PCIII. I have already confirmed that the PCIII ground wire is properly earthed, but remember hearing that a failing PCIII can cause some strange problems. My unit is over 8 years old now, but running the updated firmware from about 2 years ago.

 
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First thought was a dirty or faulty injector. Do I understand that you cleaned them after the problem started? (could still be an issue.)

Also, I would try pulling the Power Commander out of the system and re-connect the O2 sensor to see if that makes a difference; even if you have no intention to run it this way long-term. Failures or problems with PC units are not common but they do happen.

Coils/wires replaced before or after problems started? Again, a bad coil/wire could cause your symptoms. Does this happen more often in high humidity and/or rain?

If the plugs still looked good immediately after an "incident" it seems less likely that is a rich fuelling problem but could be lean. Poor combustion (bad coil/wire) would result in a crappy-looking plug but this would pretty much clean itself up after a bit of running.

I had a crappy running situation once that was traced to a semi-shorted O2 sensor; pinched in the timing cover after some maintenance. If you are running the PC with the O2 sensor disconnected, then that's not the issue. If running with the O2 connected, try disconnecting it completely.

I'm not much help here; wait until someone who knows their stuff chimes in. Good luck with it!

 
Thanks for the tips Ross.

Nothing other than changing the oil/filter has been done to the bike for over 6k miles (of flawless running) before this problem appeared.

The coils/leads were replaced with very low mileage set maybe 30k miles ago and have worked fine since the install.

I do have the O2 Sensor connected but have not done any work anywhere near that wire in a long time, certainly not before this problem showed up. But disconnecting the O2 Sensor is an easy check so will try that too.

I'll take some pics of the old plugs and post just in case but like you said they might not show anything useful since the problem is intermittent so they would get "cleaned up".

As far as I know how a lean problem feels, this does not feel lean, as I mentioned, I'd say it feels more like rich/flooded after a slow stall. But there is no indication of this in the exhaust pipes.

I also will update my original post to say that I've already checked and cleaned (with brake cleaner and compressed air) all the Injector, ECU, TPS, PCIII, fuel pump, etc. connectors - no corrosion or grease was found on any of these.

 
If these things are intermittent, it is often pretty difficult to diagnose. Easier if it quits working entirely! In addition to the stuff I mentioned above, you might want to confirm that fuel delivery volume and fuel rail pressure are correct.

 
My 07 did something like that. As mentioned before "the ground wire". Cleaned and tightened the battery connections. Problem solved. Sometimes it's the simple stuff.

 
I think pulling the PCIII is a good start at "baselining" the system to reduce as many variables as possible.

I hate to admit I've gone over to the "It's the battery" crowd, but I had a weird problem on my '07 that sounds similar and was battery related. In my case I was experiencing constant low idle speed and poor throttle response coming off idle. Researching the forum I came across lots of similar posts where folks resolved their issue by replacing the battery. I attempted to troubleshoot battery but was initially fooled because engine off voltage was fine (even after sitting overnight off charger) and the voltage at idle and 3K RPM was also as should be. Battery was kept on Tender otherwise.

I eventually discovered voltage was dropping below 9.0 volts during startup but I never had the typical low voltage symptoms such as clock and trip odometer resetting. I can only surmise that my battery's capacity was marginal and the drop in voltage during startup was corrupting something in the ECU. Before buying a new battery I was able to confirm the voltage drop was the problem by connecting a manual charger to battery and turning voltage to 14v before starting engine. Every time I started the bike with the "boost" from the charger the bike ran great with no symptoms. It's been several months since I replaced the battery and have not experienced the issue.

 
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Thanks for the tips Denver_FJR, my battery a Taiwanese version of the GS Yuasa is around 2 yrs old now and does feel a bit weak at times (highlighted with this current problem when the bike is harder to start). But I don't think its the battery in my particular case as I'd followed your suggestion and hooked up a second old but working battery in the garage to see if that would fix the problem - nope.

 
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Having confirmed that disconnecting the O2 sensor did not fix the idle stalling problem I reconnected it and unplugged the PCIII USB last night. It was late so I couldn't properly rev up the engine but it seems that the bike is idling much better now but seems to still have a bit of an occasional stumble.

As far as I know the O2 Sensor has the most impact at low RPMs so I am wondering whether at 208k the O2 Sensor might not be functioning at 100%? Are there any tests that can be run on the O2 Sensor which could confirm proper operation or identify common failures?

Despite the obvious implications of a spend on a new/replacement Power Commander I'm hoping this was my problem (or at least for the most part, the O2 Sensor is still a second suspect), will be able to confirm on a ride this weekend.

While searching for used PC units for sale I came upon this thread by Hornet Pilot where the symptoms sound very similar, and in that case the culprit was the PCIII.

 
I don't think the O2 sensor is used at idle, or at least below about 1800 RPM. During my troubleshooting I also looked at PAIR operation and on my '07 it was typically open, allowing air into the exhaust, below about 1800 RPM. There's no way a narrow band O2 sensor can compensate for unmetered air in the exhaust so the system must be running open loop at least until the PAIR system is closed off by the ECU.

 
I removed the PAIR system years ago, it's nothing more than dead weight IMHO.
Dead weight, totally agree! But the ECU doesn't "know" that PAIR has been removed, for example the ECU is still attempting to trigger the PAIR solenoid.

There are a couple simple ways to test basic O2 function but they have some caveats:

  • Remove sensor and use a propane torch to heat sensor while watching voltage. I've never tried it and some say there's a risk you could cook the sensor. Lots of YouTube examples of this technique.
  • Backprobe sensor while in system and engine running (use a high impedance digital meter). Run engine up to about 2500 RPM and watch for voltage to begin switching between about 0.1 and 0.9 volts. This requires the engine/ECU is running well enough to go into closed loop. It may take several seconds of steady throttle before closed loop is achieved. Unfortunately, if this fails it may just mean the system is not going closed for some other reason. It's also difficult to detect if sensor has become "slow". At least in my case I could see voltage switch at least once or twice a second and was comfortable it was working as it should.
 
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