Engine Idle Question


Fair play to you for sorting the problem out. I'd say you guys were close to tearing your hair out!

At the risk of being cynical - is the problem really fixed, or just worked around (for now at least)?

My worry is, since you had the problem with the original throttle body assy inc TPS, and changed that assy out inc TPS, and the problem remained... that the issue is elsewhere?
Seems strange that not 1 but 2 TBs have the same issue when TPS & ISCV are set as per the manual.

When the engine is not running, what was the previous, and what is the current, primary TPS volts?
 
I have a feeling the problem comes at how it’s being set.

I know people don’t watch educational YouTube movies or anything, but in the How to set your TPS video I showed how it’s done both wrong and right.

With you ignition on, bike not running, the TPS voltage should be more than 0.60, it should be around 0.66-0.68. The 0.60 value is when the stepper is moved to the most closed position, not the position it is set to with ignition in the ON position.
 

As @Claviger says above, its simply the settings. The spec'ed settings may be good on a brand new bike but they are now 12/13 years old, things are wearing tolerances are increasing. It was a matter of not obsessing over the 0.60/0.72 settings but using those as a guideline then tweaking the settings that work for the particular bike.

I don't consider this a work around or a cheat but a solid fix. It was a lot of time and head scratching but thats the way you learn (and I like tinkering on bikes in the garage, its my happy place).

As a similar experience many years ago I decided the carbs on my old Bonneville (I have owned for 30 years now) needed a rebuild, not for any reason just decided to. Stripped, cleaned fitted new gaskets, needles and main-jets (exactly the same spec as was already in carb). Bike ran like rubbish couldn't tune it. Refitted old needles and jets, ran like a dream, reason everything was worn at the same rate as the needles and jets so it all worked as "set". Still the same today and works, if I wanted the benefit of the needles and jets would have needed to re-sleeve, new throttle slides etc but not needed.
 

Dude I watched your vid start to end!
Wrong way = open TuneECU, moving TPS to get 0.60v when reading it under Throttle in Sensors list
Right way = open TuneECU, double click Adjust ISCV and then move it to get 0.60v, double click again and adjust nut (if required) on ISM to get 0.72v

I'm pretty sure sleeves did it the right way all along?
His fix was to move the TPS while running the engine and nail it down when the engine purred at setpoint idle speed... not going into TuneECU and Adjust ISCV and say ah fcuk it that'll do at 0.61 and 0.70v




Well I really hope you're right man and it doesn't come back to haunt you. Easy come easy go!
Wonder why did it "go" suddenly in the first place? Just wore away that quick? Funny how the other throttle body was equally as worn in.

Can I ask does your throttle % go from 0 to 100% in TuneECU's readout now? Or what's it max out at?
 
The adjustment while running I’ve seen at least one other person post on the forum they had to do, unfortunately I can’t recall where I saw it to see what the circumstances were that required it.

This whole thing would be so much easier if ECUs just had a calibrate TPS function so leave throttle closed map value as minimum, open throttle fully and save value as 100%. Similar to how PC-V does it.
 

You may ask at ALL times through this debacle the TPS on both the Tune ECU and PCV ran 0 to 100%.

The initial failure encountered was an engine stutter at around 2000rpm. And while i hate to admit it (but have no shame) from this point I ballsed it up. We also had an ECU coil fault.

The engine the other throttle body came off i suspect has less than 10K kms on it.

What we learnt is if tou obsess ovwr the 0.6/0.72 settings you may never be able to fix the issue.

May have posted this earlier but recently when a ling way from home my original TPS started hanging up and holding revs, a comnon issue on older TPS. I thought about it ans using my tablet and cable i always carry when on holiday set the TPS to 0.62 and ism to 0.74. Worked and is still on. i have a brand new spare for it but no need

As @Claviger says 0.61/0.70 "ah "f" it" it works is the oddly correct attitude.
 
Just to chime in here with a little bit of additional info, which if anything backs up the thing about not having to fret over exactly 0.60 / 0.72v

I found Triumph's software reads 0.02v off what Tune ECU and Tuneboy read wrt TPS voltages (at the same time)

e.g. Triumph read 0.58v / 0.70v when Tune ECU and Tuneboy both read 0.60v / 0.72v.
Another difference is that Triumph's software takes whatever volts your TPS is set to then adds 0.12v to it for the ISCV bit. Whereas TE & TB just say 0.60V and 0.72V, The End.

Warning: thinking out loud alert
 
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Thanks and chime away

This was exactly my suspicion, as I mentioned above, when on holiday my TPS (from 2005) started to give the usual fault signs, I jaced the voltage higher, add 0.12 to the value for the ISM and its still working like new. My reasoning was that its just a rotary encoder and has worn at the point that its 0.60vdc so you move it to 0.62V that area wil be good, seems to have saved it.

As I have a brand new spare sitting round, I am prepared to test this to the death on my bike.

My Bryant's bike is now fine also.
 

Reading comprehension is fundamental:

It shows the wrong way, and right way to adjust the idle control.
 
Had idle problem also. Would creep up to 1800 rpm after bike warmed up.dealer replaced tps runs fine now.
 
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