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Stalling, cutting out??

8K views 32 replies 12 participants last post by  CBRRich 
#1 ·
Hi guys been a while due to work.... Got a new problem I just can't figure out... My bird has developed a intermittent fault? From time to time the engine will just die, whilst riding or idling. Whilst riding though it starts to pull back and surge like it's being starved of fuel and then it will just die. I'll coast to the side of the road and the engine will turn over and after a few attempts it will start and run perfectly again either hours, days until it does it again.. Can be stopped at lights or junctions just ticking over and it will just die, after a few attempts again it will start and run perfect again. None of the electrics will die just the engine. Have checked through the loom and all seems well, checked all breather hoses and fuel hoses and all is well there aswell...any ideas before I start replacing every part on the bike to try find the fault as its intermittent? Could be fpr? Bank sensor? Fuel pump? Or hopefully something more simple? Hoping someone else has had this problem and found the source?

thanks in advance..
 
#5 ·
Sorry mate, never seen this one before. If you ride it hard it goes OK?

Your gut gut is nearly always right, if it feels like it's running out fuel then it likely is. Start with fuel filter and fuel pump delivery test?

how many miles has it done?
 
#6 ·
Thanks for the replys guys, if I ride it hard it's perfect, goes like a rocket, like I say if say I'm in 4th at 35mph you can sometimes feel it dragging and then it will start jumping and surging then just die and last night I was just sitting at lights ticking over and it just died, took a couple of turn overs and it fired back up and ran perfectly even at slow speeds?? Have checked fuel lines, breather hoses and all is clear.. Fuel pump was replaced with a brand new one last year which is oem, can't see a fuel filter anywhere? Have just ordered new fpr for 2002 bird which I believe has a bigger psi which I wanted anyway and see what that does, will order new fuel pump now just incase..

thanks again
 
#9 ·
:huh:

Funny enough it seems to be more when the tank is full but now you mention it I have noticed for a good while that it seems to perform better and smoother acceleration and feels more powerful when the tank is at a quarter full down to redline on gauge?? Or is that backwards to how it should react if it was the pump?? I'm now more confused:huh:

thanks for reply
 
#11 ·
I would suspect the fuel shutoff valve. Low rpm = low vacuum and a full tank means the membrane has a higher pressure to overcome.

Did you ever hear detonations in the exhaust when it started up again? If you did I would suspect ignition circuit ( or electrical feeding to the circuit). Otherwise fuel starvation sounds very plausible.

Not sure what the best troubleshooting for fuel shutoff valve is, but disassembly and cleaning seems straight forward and easy.

Good luck.
 
#12 ·
Well guys here's an update..stripped the bike early this morning. Took out air filter and recharged it(k&n), removed all hoses and cleaned them out(no obstructions), I did however find a strange pipe?? The breather hose to the tank had a T piece on the end with another hose coming from that that was wrapped around the inside of the frame????. Adjusted throttle cables at both ends, thought whilst at it I'll adjust balance shafts, removed injectors and cleaned them.. Put all back together minus the T piece and extra hose and just taken it out for a spin.... Feels more responsive and a lot more powerful, only time will tell if the low down death is cured though...thanks for all help guys
 
#14 ·
The T-piece and the hose wrapped around the frame but going nowhere is supposed to be there, I had the same question when I spotted it. However I don't recall that being the same hose that went to the tank?

Duck Man, does this sound right?
 
#16 ·
:thumb:Hi guys, firstly yes have done the fix. Well this morning it did it again, so thought left with 2 options? 1) roll it into the nearest river and say stuff it. 2) get back to basics and strip it. Just to note I chose option 2.... Removed the tank, injectors, throttle bodies, throttle cables, all hoses, removed fuel pump and stripped it down, firstly found sand in the pump, completely cleaned it all out. Then I noticed the pull cable screw on the throttle switches had no thread and was really loose, straight on the phone and called local salvage yard and picked up another switch housing. Cleaned all the hoses,injectors and tank. Put it all back together, set the cables rerouted the hoses and took it for a spin... Yep that has most definitely done it.. The torque and power was never like that before, it takes of before you realise you've touched the throttle, easily does 30mph in 6th and the tick over is perfect. Fuel consumption is a load better aswell.

Just to to mention I left the T piece off and just used the single hose routed down by the gear lever. I've an idea(theory) :confused:about that hose and will post once I've checked it out in the morning and put it to the test...

thanks again for for all the suggestions....:thumb:
 
#17 ·
I have something very similar happening on mine. In my case the symptoms first appeared as bucking like it was losing ignition or fuel when I was at cruise. Idle and acceleration were fine, only when the throttle was in one position did it run poorly. Today after extensive troubleshooting it did the "sudden off thing with the FI light" 3X before I could make it around the block, scary (I could have broken something in the process). I'll try to pull codes tomorrow if there are any. Reddave's comment about "throttle switch" (what is that?) made me wonder could it be a TPS with a dead spot?

One other thing I found when I was troubleshooting was high resistance in the key ignition leads that would decrease if you cycled it a few times. Since everything goes though that bad contact would certainly not help by creating low voltage downstream. You would never expect to see that in such a simple switch.

I'll also go through all the other switches, I cleaned and put dielectric grease on the engine cut off switch and the turn signals. Interestingly, the turn signals were erratic this morning and they have always been reliable. I'm going to cycle all the switches and see if that helps.

Any other ideas?
 
#19 ·
This very thing happened to my bird today. Going along at about 45mph I felt what I thought was a brief cut-out. Since it's never happened before and I thought I hit a small bump at the same time, I forgot it. Around 20 seconds later, engine dead. Luckily I was able to pull into a small store lot. Put the bike on the side stand, hit the ignition and, no codes. Hopped on, and it started right up. It happened again as I was making a left-hand turn in front of on-coming traffic and luckily had enough momentum to get across.
Intermittent driveability problems are the hardest things to diagnose. Especially ones which don't throw any codes into the computer. The way it cut, felt electrical. Instant. Then on re-start, no hesitation, it just lit.
Someone's going to have to expand on this stator being the fix. If the bike stops charging, then the battery takes over. Nothing instant. I remember the FJR could have a problem with the ignition switch wires. Mine didn't, so no experience there.

I'll watch for any responses, and hope that this doesn't kill me in the mean...
 
#22 ·
Found it strange myself?? Think when it was happening the stator must of been packing in but not died completely so just enough to keep it firing.. its when I pulled up and ignition off then back on and the battery was flat I tested it and it must of finally give up.. that's the only thing I think could of possibly being happening??
 
#23 ·
It definitely acts like a solid state problem not determined by temperature or speed. On the one where I was making the turn, I cycled the ignition and hit start, and it fired right up. I'm going to go through all the wiring at that switch. All those wires are cleverly hidden and routed, so It may be hard to check them when I'm out and it happens again (which I hope doesn't)
 
#25 ·
Good News: The 3X stalling was traced to the sidestand switch. The bike has flawlessly since then..until Friday.
Bad news: I put a brand new battery in Thursday (should not be related), drove it to work and was heading home when I was coming up a hill and got that "something does not feel right" sensation. When I rolled off the throttle as I crested the hill the bike died FI light on. Light stayed on for would not start. After about 5 seconds the light went out, I could start it. Drove a few more hundred yards, cut out again. I managed to limp it to a friend's house and came back the next day to troubleshoot.

Next day, like others have noticed, no codes. Got it running and started to drive it again, still cutting out. This time I kept it moving, if revs/speed was low it would cut out, FI light on and kick back to life after a few seconds.
Once I got out on the highway I was able to keep it from cutting out (no FI light either) but it had that "something does not feel right" sense the whole way similar to what started the whole thing.

One more thing: Both turn signals were not blinking and would come on solid but dim. I was able to make it home, had to stop 100 feet from my house and it would not restart. Pushed it into the driveway. With the ignition on I could hear the turn signal relay "buzzing" if actuating either L or R turn signal. Unplugged the relay and checked the voltage on the plug: Oddly I was reading ~3V on the green.

After the first time this happened, I pulled every connector apart in the harness (including the (3) junction blocks wrapped up in the loom) cleaned and dielectric greased them. Checked every sensor per the manual (that I could without the break out box) all good, I could find no corrosion, burning, or any of the usual suspects something is bad. Checked the TPS which initially showed a "blip" with a digital VOM, I could not duplicate it with a analog VOM so it may have just been the meter.

This weekend, I took the bike apart again and checked the two mid harness blocks because I remember one had all the grounds and I suspected there might be a backfeeding involved, again found nothing. However, once I taped everything back up again, the turn signals were working. Voltage on the green was now a fraction of a volt. Maybe I should do the "Loom fix" even though there is no obvious problem?

So my question for my fellow sufferers is has their turn signals been part of their symptoms?

So my go forward plan would be to do the loom fix on all (3) blocks just to get them off the list (Part of my concern is the more I man-handle the harness, the more likely I am to create a problem as much as fix it). After that is a new ECU the likely problem? PS I have HID lights on my bike, someone suspected that could have caused a surge to the ECU and damaged it. My thought is that if it had, would it not be all the time or not at all? This type of issue seems to be more a like bad connection than anything.

Thanks for any ideas of what to do next.
 
#28 ·
My bike did that once, it went dead for a second, sprang back to life, then a few seconds later just cut out. I was coasting down a hill and it was easy to pull over. I was going through a code 25 issue at the time, but I now think this was unrelated.

I had previously checked and cleaned the loom and the ECU connector, my ECU was also strapped down, again checked because of code 25.

In my case at the suggestion of folks in here I pulled the RHS switch block off and cleaned the start and kill switches. They were pretty grubby. After cleaning, I coated everything in dielectric grease, masked the switches off and put some silicone spray on the throttle tube and from that point on I had a whole new bike. It has never done it again, although I should respectfully point out the ECU has since been changed.
 
#30 ·
I did the "stem to stern" cleaning: Every switch, every connection, every sensor was gone over. It took about a month of Saturdays. It ran great for about 2 weeks and then went wonky. The weird thing about the directionals are now they are working and I don't know what I did to bring them back. If you look at the wiring diagram the lights and the FI system are pretty much separated (for good reason I'm sure). However there is the grounds that all eventually have to come together and back feeding through the circuits can happen. This is all further validation on why I did not want to become a Electrical Engineer. I'm taking the VFR (don't get me started on charging issues with that) on our Fall trip, the BB would have been better for the long haul. Bummer! I'll get into it again when I get back and keep you informed, it will be interesting to see if it is OK now that the directionals are working again.
 
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