Intermittent stalling on the freeway.

[ionbeam]

I put new plugs on and switched out a very dirty air filter (Could'nt see light through it). Haven't had issue since. Thanks everyone.

The issue may have stopped but what you did shouldn't have cured the symptoms you reported. Anyhoo, glad it's running right again.

 

[HawkWing]

I want to join the discussion here and add my $.02:

My 2008 (42k mi) ran pretty much flawlessly until around 35k, then developed the same symptoms as OP's bike.

Symptoms: Engine intermittently, repeatedly, irregularly, and briefly (1-several seconds) "cuts out", or stalls (as in, "dead as a doornail), usually, but not always, after cruising for an extended period at the same rpm. Never occurs before bike is ridden 60-70 miles (until yesterday- after 20 mi.), and more often than not, not even then. Always occurs after continuous 200+ mi. rides. Occurs in 4th and 5th gears (but could likely occur in other gears, if I cruised long enough in one), usually around 4-5k rpm. If the engine fails to "revive" on its own, I can coax it to resume power by downshifting and giving some throttle.

Seems to happen regardless of temperature, fuel octane rating, road or other external conditions. What seems consistent: rpm= 4-5k, engine has been running continously (and smoothly) for an extended time at the same rpm (never during acceleration, or changing rpm's).

I have previously done fuel cap maintenance; no effect. Have added RR's harness, Barbarian jumper mod, inspected/serviced ground spiders (pristine), various farkles. Have not checked harness grounds(except when I installed RR's harness); replaced battery less than 500 mi ago, which has not stopped the prob.

I am very motivated to cure this problem (imagine your ride stalling at 80mph in 4 lanes of steady traffic, and you'll understand where I'm coming from); and will be willing to try whatever (within reason, cost, ability, and time-wise!) the gurus suggest. Oh, BTW, I am, for the most part, an electrical jackleg. But I do have a good analog meter (and a cheapo HF digital), and can generally tell the AC's from the DC's. (apologies to Firesign Theater!). With winter around the corner, it's time complete some other maintenance as well as get this aggravating (and unnerving) glitch resolved.

Please advise with request for other info, or suggest a course of action. Right now, I lean toward a TPS malfunction or grounding issues, but these are only a hunch.

 

[RaYzerman19]

I've had this occasionally and first thing I suspect is water in the fuel, especially if you're taking a week or two to use up the current tank of fuel or bike is sitting. Phase separation might be occurring or there was water in the fuel at the pump (was the tanker truck there or just leaving when you filled up.....). Try some Seafoam first, never hurts. See if it's cured with the next tank of gas. Best to attempt cures one at a time so you know which cure solved it.

If commuting, your gas tank gets all warmed up and cools twice a day in short distances like 20 miles. Could also be sucking in humidity via the vents.

 

[HawkWing]

Rayzr, I'm discounting fuel issues, as the problem occurs across a spectrum of fuel conditions: full/low fuel level, low/high octane, with/without a variety of fuel treatments (including Seafoam), through many tankfuls of fuel from lots of different suppliers (7-8k miles worth).

Almost always parked inside or in carport. TN is humid, but I would suspect that the prob would be more widespread if humidity was the cause. Bike is used mainly for short commutes- 20mi., twice a day. Only once has the prob occurred during this commute- that was Tues. Bike usually needs to travel farther before prob occurs- >100mi.

One clarification as well, to my original post #21: while the engine does quit completely (i.e., the power loss is sudden and complete), there is no loss of power to the instrument cluster or lights. Clock/tripmeters do not reset. No codes thrown.

 

[Hornet Pilot]

Do you have a Power Commander installed?​

 

[paulo888]

Hawk, Before I worked at a motorcycle store, I would have never guessed that an air filter would make a bike run horrible or not run at all. This is a common problem. Check your air filter to see if it is as dirty as mine was.

 

[NMRoadRunner]

I belive this happened to me on a ride last Sunday. Kinda felt like it did before the ECU swap out recall. When rolling off the throttle a slight amount engine would cut severly, and roll the throttle on would give no imediate response until, zoom, it would take off. Maybe TPS problem. This occured occasionaly during the first 20mins, then stopped, didn't act up again even though I tried to duplicate conditions. Puzzeling.

 

[RaYzerman19]

It's good to get the fuel issue out of the way first, now sounds like something happens when it's hot. Could be sudden breakdown with heat or vibration, results in sudden cut of the ignition/fuel intermittently. Is sidestand switch OK/loose? It could break down with heat. Emergency stop button working properly? When the engine cut happens, assuming you could pull the clutch and coast, would engine resume at lower rpm or just stay shut down? If it shuts down, can you restart with the starter button? Or will it restart with an ignition off-on cycle (don't do that while coasting)? Ignition cycle will reset bank angle sensor and ECU.

It's likely not spark plug or coil breakdown as that should only result in loss of power, poor performance, not all cylinders, not sudden engine cut completely. Next steps could take several directions.

 

[Geezer]

It's good to get the fuel issue out of the way first, now sounds like something happens when it's hot. Could be sudden breakdown with heat or vibration, results in sudden cut of the ignition/fuel intermittently. Is sidestand switch OK/loose? It could break down with heat. Emergency stop button working properly? When the engine cut happens, assuming you could pull the clutch and coast, would engine resume at lower rpm or just stay shut down? If it shuts down, can you restart with the starter button? Or will it restart with an ignition off-on cycle (don't do that while coasting)? Ignition cycle will reset bank angle sensor and ECU.It's likely not spark plug or coil breakdown as that should only result in loss of power, poor performance, not all cylinders, not sudden engine cut completely. Next steps could take several directions.

Actually, you can switch off the key while coasting and then switch it back on. I have done this a few times to reset my radar detector after it gets confused. I normally just let the clutch back out to restart the engine.

 

[HawkWing]

Do you have a Power Commander installed?​

No PC.

 

[HawkWing]

Hawk, Before I worked at a motorcycle store, I would have never guessed that an air filter would make a bike run horrible or not run at all. This is a common problem. Check your air filter to see if it is as dirty as mine was.

Will check by this weekend (or before if I can) and report back. Original was replaced @ maybe 20,000 mi; cleaned once after that @ 30k.

 

[HawkWing]

Ray: I'll take a stab at your questions/comments:

1. Is sidestand switch OK/loose? - Feels secure; plus the first/last mile of my commute is over a rather rough, bumpy road/driveway, where I would suspect the prob would manifest itself if the cause lay in a mechanical issue with sidestand/switch. The switch will cut off the engine when in gear/sidestand down, but not in neutral. Heat breakdown a possibility- any way to test, like heat it with a heat gun? (don't want to damage a good part)

2. Emergency stop button working properly? - As far as I know, yes. It will cut off the engine when engaged. Will see how sensitive it is by this weekend (bike is at another location right now).

3. When the engine cut happens, assuming you could pull the clutch and coast, would engine resume at lower rpm or just stay shut down? - this has occurred, and the engine always resumes AFTER downshifting into lower gear with throttle movement. Usually resumes on its own with little or no throttle movement (shutdown is brief and transient). During the few longer shutdowns which have occurred, I can't say that I've simply pulled the clutch then re-engaged it without downshifting. But I can say that the bike has never died long enough for me to come to a complete stop, so I have not had the luxury of pulling off the road, coming to a stop with engine dead, then attempting to restart with starter. Worst case scenario so far is: bike cut out about 80mph, failed to restart after downshifting two gears, slowed to around 20mph (on shoulder in traffic) then restarted in 2nd(?) gear. I have always been giving it throttle when it restarts: never had it restart with no throttle- @ idle.

4. Or will it restart with an ignition off-on cycle? - Don't know the answer yet, but if it gets bad enough I will definitely coast to a stop, ignition off/ignition on cycle, and see what happens. (Hope it'll restart!)

One serious drawback to all this is that the longer the bike has been continuously running, the more likely an event will occur, and the more likely that event is to be of longer/more serious duration. It seldom occurs at less than 100 miles a stretch, and then of only slight duration. This may be a prob which will take putting on some mileage to diagnose. So, I'd like to bench test/investigate as many possible causes as I can before really putting it down the road for a few hundred miles. I know this may not be the method to pin down the exact cause, but I want to fix the prob in as few hundred/thousand miles as I can.

 

[HawkWing]

I belive this happened to me on a ride last Sunday. Kinda felt like it did before the ECU swap out recall. When rolling off the throttle a slight amount engine would cut severly, and roll the throttle on would give no imediate response until, zoom, it would take off. Maybe TPS problem. This occured occasionaly during the first 20mins, then stopped, didn't act up again even though I tried to duplicate conditions. Puzzeling.

Yeah, very similar to mine, except in my case the cut occurs after prolonged steady throttle, but will resume usually with some throttle input. I lean to TPS, but I assume there's no way of knowing without TPS replacement. Willing to check other possibilities before I start random replacement of parts, which is not the forum-recommended method (and can leave one with a pile of good parts and the same damn problem).

I'm interested in any further issues you may have along this line, and other thoughts.

 

[HawkWing]

Is it a stumbly type of thing or does the engine just outright quit. What does it take to get it going again?

Indeed, very good questions that are key to sorting this out. Assuming (always a bad thing) that it is like a light switch, running, not running, then running again, definitely check the battery cable connections.

Does it do it only when cold or only when hot or it doesn't matter? Another big clue, does it do it always at the same RPM regardless of gear?

Just to make sure I clearly describe my prob: It's on/off like a light switch- battery connections are confirmed at battery; ground should be good to frame, but will inspect.

Happens only when fully warmed/hot.

Always occurs at same RPM in 5th or 4th gear. But could perhaps occur in lower gears with prolonged steady cruising.

 

[HawkWing]

OK, here's my plan of action for this weekend:

Check battery connections- where? @ battery are confirmed good. will check ground to frame. where else?

Side stand- inspect closely for operation/mechanical issues, inspect connector to harness.

Kill switch- check for sensitivity, connector.

Air filter- inspect/clean.

ECU connector- inspect/reconnect.

Ignition switch- not sure what to look for.

Tank vent- confirmed OK.

Then take her out for 100 or so miles and see what happens.

Report back here.

Anything else to look for at this point? Any thoughts about troubleshooting the TPS?

 

[RossKean]

Intermittent problems (especially electrical) are always difficult. Based upon the symptoms, it sounds to be electrical rather than mechanical. If it gets worse, it will be much easier to find and fix. My guess would be ignition switch - might be worth taking it apart and having a look at contacts and solder joints. Alternatively, you could run a jumper (switched) around the ignition and see if you run without symptoms for a period of time. Possibly a throttle position sensor but I wouldn't think (might be wrong) that there would be a dramatic off-on behavior. Good luck with it and be sure to report back with your findings.

 

[Donal]

OK, here's my plan of action for this weekend:Check battery connections- where? @ battery are confirmed good. will check ground to frame. where else?

Side stand- inspect closely for operation/mechanical issues, inspect connector to harness.

Kill switch- check for sensitivity, connector.

Air filter- inspect/clean.

ECU connector- inspect/reconnect.

Ignition switch- not sure what to look for.

Tank vent- confirmed OK.

Then take her out for 100 or so miles and see what happens.

Report back here.

Anything else to look for at this point? Any thoughts about troubleshooting the TPS?

The simplest way to check the TPS is to use the inbuilt diagnostic system. This will only tell you that the TPS is working at that moment in time and your problem only manifests itself as clearly described in your posts.

 

[RaYzerman19]

Perhaps I should have explained better... the idea is to see if the engine will resume running at idle, i.e., clutch pulled so no help to keep the engine spinning from momentum or lower gears, and no throttle. If it resumes, that would point to a sensor or perhaps inadequate fuel volume at higher rpms, air volume (plugged filter) or even ECU. The opposite also can be tested.... will it repeatedly die at higher rpm (again, fuel volume/air volume). IF it won't resume, then points to more on-off things like fuel pump relay, side stand switch, ignition switch, kill switch, bad ground. We also don't yet know for sure if it is heat related......

The side stand switch is right beside a big heat source... mine had a goofy piece of foil glued on by Yamaha presumably as a heat shield. However, I've never had occasion to dig into one to see if you can put contact cleaner, etc. in there. It can be tested though, while cycling the side stand to ensure it works when side stand is up/wiggled around. Test immediately after a hot ride, as I wouldn't attempt any other heating that you can't control. Kill switch has no heat, but can have intermittency if gummed up, this is servicable. Ignition switch, also no heat, can be tested for intermittency just by playing with it and see if the fuel pump recycles and the gauges sweep in the run position.

Other things affected by heat are the TPS and MAP sensor, cylinder identification sensor, causing the ECU to not have inputs momentarily. TPS could be bad in one spot at a certain throttle position (4-5k rpm). If it happens in 4th or 5th at the same rpm, then it would seem not speed related for example.

So really, the idea is not to go replacing expensive bits until it's narrowed down. Also not to replace/repair a whole bunch of things at once, 'cuz all you learn is "yep, must a been one of those things that fixed it, I dunno which one". Anyway, agree with your weekend plan. If you do get another repeat, keep us posted on how/if the engine resumes while coasting, clutch in, no throttle.........

 

[ionbeam]

If it is the TPS it will be bad in the same narrow RPM range regardless of gear. If it is the TPS, once off the highway you should be able to recreate the problem in any gear over and over. In fact, it should never, ever run well at that one small RPM range once hot. If the TPS is bad the output voltage will drop significantly making the ECU think you are at idle or worse and adjust fueling for that condition causing lean misfire or bucking, not a clean dropout.

If possible, it sure would be good to know what happens to the RPMs when you have a dropout. A stone drop of the needle to zero RPM would tell a story about what the ECU is thinking and doing. A quick pop UP of the RPM would be a strong indication that your FJR is popping out of gear under load and popping out of gear will create the same symptoms you are reporting.

 

[HawkWing]

Thanks to all for sharing expertise and advice; I will get it digested and now have a much clearer idea of what symptoms to look for, and what to do (clutch in/no throttle) and observe (tach rpm, e.g.) the next time they do occur. I will complete the checks I listed above, then later disassemble/inspect ignition switch, kill switch.

Ion, not sure about tach reading, but the engine APPEARS to be dead; observing the tach should give a definitive answer. I will also get off the road and shift to lower gear (2nd?) to see about repeating the prob in that gear, at a slower speed. It has occurred in 4th, but usually at highway speeds in 5th. Making observations depends, of course, on the prob rearing its ugly head long enough (they are usually transient) for me to make some observations. Hopefully, not in traffic.

Ray, is the pump relay something that can be inspected easily, without removing fuel pump? I will inspect fuel pump electrical connection.

I will be back with more info as soon as I can make some meaningful progress/observations.