Backfiring, stalling, and throatier than usual | Page 3 | GTAMotorcycle.com

Backfiring, stalling, and throatier than usual

So the PC is still connected eh?
Ya PCV is still connected. You really think that's the issue eh? Maybe I will prop the tank, take air boxoff again and put back in the stock connectors to injectors. I have my mind set on an intermittent electrical issue/short/ground/switch/sensor issue. Pisses me off though because when shes running good, shes running goooood! So Mechanically everything is peachy
 
hmmm. I think you made a thread not long ago about your wiring harness being in the wrong position and lying on top of the rad? Add to that the missing bolt you described and me wonders what has gone on around there. Check all the connections that could be affected by movement or vibration...and make sure there are no melted wires from the harness sitting on the rad ? Do this while you have things opened up to replace the missing bolt. best luck.

EDIT and take your bike for a longer ride w the pc disconnected.
 
While you're checking things, you might as well look at the throttle position sensor too. I had one go bad and it caused driveability problems at part throttle, including backfiring/"sneezing" through the airbox.
 
I cleaned a connector under my stator that was completely gunked up. It leads towards kickstand switch and gear position switch. I temporarily stuffed a rag towel between the battery and the frame so there is no more wiggling/bouncing around of the compartment that contains battery, wires, ecu, and main relay. Went out for a ride for over an hour last night afwards and not one single hic up. Bike was running beautiful. Fingers crossed either one of the things i did fixed the issue.
Only time since the issue started the bike ran that well for so long
 
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Update folks.
I have put about 150 km on my bike since Friday evening. Haven't had a hiccup since! It was either the loose compartment under my seat causing the battery, ECU, and main relay to get all wacky, or the gunked up connection that leads towards kickstand/gear shifter was cutting out.
Electrical can be a nightmare....it can be something so little that can cause such antics.
 
Has anyone here ordered used parts off Ebay? There are some used throttle body's guarantee working condition for just over $100.00...beats paying the $1500.00 new OEM price!
The majority of the issue has disappeared but I had a code 62 FI light pop up "sub throttle valve actuator". I am unable to purchase this part as it is specifically positioned from the factory. My rpm got stuck around 4000 and wouldn't drop while in neutral, and when i was shifting gears the tack didnt really drop much at all (I am assuming the sub throttle was stuck open, where the main throttle body was still working fine). Turned the bike off/on and it ran fine again like nothing ever happened. It happened 2 times in 200km or so. It also intermittently wants to stall when it's idling and I blip the throttle (assuming subthrottle getting stuck closed for a split second),....not all the time, just here and there. Bike almost feels choppy when im slightly on the throttle, and backfires when I am lightly off the throttle,, but when I crank it open she runs like a dream.
Just kinda debating whether or not to get the throttle body assembly as its very intermittent, it's not an issue that is always happening.
What do you guys think, take it to my mechanic and get him to do a throttle sync before biting the bullet on a used throttle body? After doing some research, it seems like the issues I am experiencing are pretty related to the throttles being out of sync.
 
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There are some used throttle body's guarantee working condition for just over $100.00 sounds like a deal if the injectors are still on them, that's for sure.
and no I never ebay.
 
There are some used throttle body's guarantee working condition for just over $100.00 sounds like a deal if the injectors are still on them, that's for sure.
and no I never ebay.
I plugged my laptop into the pvc software and let my bike idle. The tps seems fine. If it was bouncing around or in a (-) or + position at idle I'd get it looked at.
The subthrottle valve is electronic on my bike where the main throttle is wire.
Ride 60km last night with not a single hic up so I'm leaning towards and electrical problem or an issue with my map that my tuner put on. I'm gonna throw on the off the shelf map for the m4 slip on and see how it rides.
Just driving me freakin nuts how it comes and goes. After reading on kawi forums if it was my subthrottle valve actuator it would constantly be giving me issues and throwing the code... Not every here and there like it is now.
My injectors were all tested and were in spec, so if I was to get the throttle body I'd just swap the injectors out into the new one.
Ughhh
 
Or thrown on a zero map. Factory map should be fine for a slip-on, at least for testing purposes. This will rule out the PCV map, which doesn't necessarily rule out the PCV itself...
 
Or thrown on a zero map. Factory map should be fine for a slip-on, at least for testing purposes. This will rule out the PCV map, which doesn't necessarily rule out the PCV itself...
The M4 Slip on deletes the cat on my bike. My friend with same exhaust as me on a 2012 (same bike) didn't have a map on it....ran like a bag a crap, well not as bad as mine does intermittently, but ya, not good at all.
 
Yes, it won't run perfectly, but at least you can see if the problem persists when the PCV (theoretically) isn't modifying the stock map. I say theoretically, because you can really only rule it out after removing it as has been suggested previously.
 
Update!
Bikes been running great after I replaced the missing bolt under the gas tank that connects the tray where battery, ecu, and main relay sit in (1000km or so). No connections were rattling around anymore under the seat and all was good!. Well darn...it came back to haunt me last night!! Every time I went over a bump the throttle would slightly cut out, then I hit a nice bump and bam, backfire, misfire, just running like a bag of ****. Instead of turning the bike off I pulled into a parking lot and took seat off. Moved the main harness around and there she goes...bike wanted to cut out every time I moved it. Then I really moved the harness and the bike cut out completely. Turned the bike back on and same thing... Anywhere on the main harness whether it be near the relay or down closer to the gas tank/around the rpm's would drop and then when I moved it with a tad more force the bike would stall.
Turned bike on for a 3rd time and absolutely nothing happened when I moved around the harness...like absolutely nothing was wrong with it, tt was running fine, no matter how much I moved the harness, in any spot.
So ya, nailed it down to an intermittent short in the harness somewhere. Time to cut away all the tape and see what's going on. I was looking at pictures of used wiring harnesses, and there are two pin hole connectors with black and yellow wires, right near where the main fuse is on the harness. I think these may be secondary grounds? Was looking in the service manual, but I was getting lost with the wiring diagrams and couldn't figure it out. I can see these either mounting to the side of the frame, or under the gas tank near the main fuse. Wouldn't be surprised maybe those grounds (if they are grounds) are the culprit. Similar to when you have a bad ground on the negative battery terminal....it can run perfectly fine, but once you go over bumps and the ground loses connection the bike acts all wonky until is makes connection again.
Super happy I nailed it rather than replacing a ton of sensors, parts, etc.
Wish I could post a video, but I can't figure out how.
Ill keep you posted when the electrical gremlins from hell are found. This has been driving me nuts as it's so intermittent and you can only try to figure out what the issue is when it starts acting up. On the plus side, I've learned a ton about my bike trying to nail this down.
 
Does the bike have a Bazzaz ZFi by any chance?
Nah I have a power commander. The TPS tap wire is solid (was moving it around last night and nothing happened until I moved the actual harness). I have ruled out the PCV. It's an intermittent short or ground somewhere in the main harness. I'll check what i belive to be secondary grounds first. Then start slicing into the harness.
 
I had a similar issue on my S1000RR last year (or the year before, can't remember) and it was a loose ground wire from the Bazzaz unit. Glad you got it sorted out though. Ride safe!
 
The PCV ground directly to the negative battery terminal and its solid, along with the Throttle Position Sensor tapped wire. Haven't sorted it out yet, I just at least have an idea of where it's coming from. I can still ride as its so intermittent and won't cause any issues until the connection or short happens again (it's running fine atm).
If I can't figure it out on my own I'll just take her to the shop and get it sorted out.
Thanks!
 

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