Throttle position sensor symptom 16es

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Joel S.

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Sep 24, 2016
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Location
Twin Cities Minnesota
hey all, chasing a problem here, The symptom is a big lurch, hesitation, surge, like turning the bike off. past the throttle point, the bike runs great, seems to happen when the tac is about 3k, maintaining very light throttle. it's not a misfire or anything, but a big off then on, smooth cutting in and out,

I did the brake fluid flush, and jumping the abs to actuate the pump, at that time i felt the battery cables, looked clean and tight, no other electrical issues. The bike has about 24k miles, so if it was the programming fuel cut, i figure i would have felt it before this year. i have ordered the obd2 cable so i can watch live data, i have a couple nice scanners and a bluetooth one also.

My background is a 25 year ase master mechanic, cars and light trucks. i do have the YES extended warranty but thinking sweeping or recording a test ride, then replacing the sensor if bad will be much better for me than doing the dealer battle, 2,4,6 weeks to possibly correctly diagnose, replace, and confirm the repair while not charging me for things that do not fix the issue. It sounds easy enough, but this location sure doesn't seem to do well with dealer service.

does these symptoms sound like i'm on the right track ?? still newer to fjr compared to others, i do have the service manual,
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i have done forum searches and reading, and it seems like a good probability.

thanks so much for any time or advise here. i greatly appreciate it.

Joel

 
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You got it. Sent you a pm.

Too bad mama yama hasn't fixed this yet.
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My symptoms were different - engine intermittently missing at around 3k rpm. The problem showed up around 35k kms. It was hard to tell if the missing was getting worse or I was noticing it more. I had just headed out on a cross country when the symptoms became more consistent. From reading this forum I knew that the TPS had been an issue. A friend tried to get me a new sensor so I could install it at one of my stops, but Yamaha Canada said they didn't have any, and had never sold any for gen3 bikes. So I finished the trip and the problem didn't get any worse. Once I was home I did a careful throttle balancing etc and the issue remained. The TPS had always checked out OK on the diagnostic screen, and it looked good on an ohmmeter as well. But I replaced it anyway and sure enough no more issues. On gen3 bikes there's an additional nearly identical sensor (right side, in front of the airbox) rotated by the throttle cables. Seems like that one is as likely to fail as the TPS although the symptoms may be different. BTW, I ordered my new sensor from Partzilla, so Yamaha Canada still won't be counting mine as failed.

 
TPS failures happen on most any bike that has one. With Fly-by-wire throttles we are unlucky enough to have two of them. One of them registers the position of the hand throttle, which is sent to the ECU as a command signal for the throttle servo positioner, and the other TPS device is on the end if the throttle shaft as feedback to the ECU to tell it where the throttle is. Failure of either of these position sensors could cause the kind of herky jerky throttle control you described.

One clue is that TPS devices tend to screw up, at least initially, after being heat soaked. If you find that the symptoms disappear when the bike is cooler, but come on again when youve been running it hard for a while or in high ambient temps, it is quite like to be one of those rotational sensors.

 
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thanks, i read that the other day, pictures are great.

guessing i'll use the obd2 and scanner to set mine,

thanks all for the conformation i'm on the right track. i appreciate te feedback.

sounds like a self repair vs a warranty claim is the way to go too, it won't take me 2 or 4 or 6 weeks to try to fix.
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raesewell, did you replace yours or just clean it with a crc contact cleaner or something ?? any details on your procedure and results (cleaning, not the r&r) thanks
 
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I just cleaned mine with contact cleaner, give it a good spray and rotate it through its full motion a couple of times. Did mine again recently. seems to go for about 20,000 miles.

 

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