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one side not firing after removing fuel tank -- r1150gs 2001

jeks

New member
so, I replaced my brake lines the other day. putting the bike back together its not firing on the right (brake) side cylinder.

I checked the usual suspect throttle cable not seated, no luck.

checked to see if it has spark... spark plug looks nasty but it is sparking. I replaced it as well.

swapped the coils, same effect left side ok right side no good.

im wondering if the 2 fuel lines coming out of the tank are one per cylinder? there are some quick disconnects there and it seems like the simplest thing is if one of them is not working esp because it is something that changed during the job vs. mysterious failure of something else by coincidence. ( but I don't know for sure if this is how it works.)

any tips on other things to check and how to further test the fuel delivery most appreciated.


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No, the two lines are not "one per", one is the output from the pump and the other is the return line. GSAddict has several posts in these threads about how to verify fuel pressure and the lines' hookup, do a little search.
Here's a picture; I forget the source.

You say you swapped the coils, so I'll presume you have the "twin-spark" version (2001 was during the change from single plug to dual)... Look closely at the little plastic connector at the top of that coil - they are known to crack.
 

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when I say I switched coils, I swapped the spark plug wires on the coil between the alternator and the computer
 
if I messed up the non fuel lines could I have f’ed it up? I didnt mark them before taking apart.
 
1) Just for clarification - so the coils themselves stayed where they were, on top of the plugs? "Maybe" a weak coil on that side, another known issue (difficult to test without another spare new coil); also possible that the pins inside the connection at the top of that coil are narfed.
2) Not likely, that would affect both cylinders.
 
im sorry if I am using vocab w/o knowing the precise meaning. I took the tank off and swapped the ends of the spark plug wires that connect between the FI computer and the alternator
 
Not a problem (yet...), we'll get you edumacated!

So - are you saying that you swapped the spark plug cables at the coil? (under the forward part of the tank, below/behind the "neck" of the frame) (the alternator really isn't a part of this, it's just local to the scene)

If that is indeed the case, then that would point more to a fueling issue than an ignition issue, since the one coil fires both plugs at the same time.
 
yes thts wht I did, swapped the spark plug.cables at the coil, which made me also think it was fuel since it has spark, and why i became suspicious of the quick release doohickys bc they were involved in the original “fix”
 
Please make sure the fuel injector is plugged in. It wouldn't be the first time that I accidentally unplugged it while messing around over there. I know you say you don't have spark, but you also alluded to possibility of there not being fuel. Give it a shot. And good luck

Sent from my SM-T837P using Tapatalk
 
Please make sure the fuel injector is plugged in. It wouldn't be the first time that I accidentally unplugged it while messing around over there. I know you say you don't have spark, but you also alluded to possibility of there not being fuel. Give it a shot. And good luck

^^^^^^THIS^^^^^^^

Plus, swapping coil leads at the coil eliminates a dead port at the coil, but doesn’t eliminate the possibility of a bad plug wire.
If the RH injector connector seems solid, pull the injectors one at a time and crank the bike while holding the injector in an old milk jug or other plastic container—see if you’re getting a nice conical pattern from each.

Best,
DeVern
 
Bad injector?

Just as you swapped the coil try changing the injectors around. Put the left one in the right side and the right one in the left side. If your dead cylinder follows you have found your problem.
 
fixed!

thanks all for the tips and encouragement.

as I was checking the injector, I noticed the terminal was missing! I suppose this wire got tugged on, either removing the tank or while we were working on brakes. took the boot cover off and pulled the terminal/wire back into place. back in biz.

what a relief!

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If I remember correctly, Chris Harris has a YouTube video that had the exact same issue with the F/I connector pin backing out.
 
Tessa tape can remedy that for the future

You should look into getting some Tessa Tape and wrapping those loose wires up. It help prevent similar problems and it would clean things up a little.
 
You should look into getting some Tessa Tape and wrapping those loose wires up. It help prevent similar problems and it would clean things up a little.

thanks I will spare the thrilling photo of a wrapped wire, but it does indeed look cleaner now. good tip.
 
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