Chasing gremlins

jake shaw said:
Just a thought. Which TPS did you replace? The one at the rear of the throttle bodies (primary) is the one for idle.
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The one at the rear. Based on my initial diagnosis, and the little reading I did, that seemed the most likely culprit. Im still pretty sure, after a little more reading, it's the TPS but just needs to be adjusted.
 
It's also strange there is no MIL or even error code in the scanner. As poor as it's running, it should absolutely be throwing a code
 
R-III-R Turbo said:
Good to see the 2.5.5 download on here is still helping people out.
First I'd say to set the primary TPS up correctly, it's not going to work by guessing, has to be done right. The 0.62v on that screen isn't right. It's to be set to 0.60v at one point and 0.72v ar another when on the ISCV Reset screen.

This video should help;


When that's done, can you 'reset adaptives' then run the bike without touching throttle, to do the 12 min tune (not really a tune btw but forces adaptives), where you let it idle until fan comes on then leave it run another 12 mins, all with TuneECU connected and watch the throttle balance screen.
And report back what numbers you see, particularly if the bike starts bogging and dying.

Also - can you see what map is on it?
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I just realized I watched your video, to start diagnostics on this bike!
 
@R-III-R Turbo knows this stuff in and out- stick with him. For some reason a couple of things also come to mind. I believe it was @warp9.9 who recommended shimming the TPS so it doesn't stick. I remember using a beer can for material and doing that the last time I replaced the TPS issue when I had the Roadster. Also, along those same lines, be sure that you don't over tighten the TPS. It calls for a very low torque value. Just throwing that in there. In addition to the things you mentioned I'd add fuel filter and, if the original air filter system as been replaced look for cracked caps on the throttle body.
 
Journeyman said:
@R-III-R Turbo knows this stuff in and out- stick with him. For some reason a couple of things also come to mind. I believe it was @warp9.9 who recommended shimming the TPS so it doesn't stick. I remember using a beer can for material and doing that the last time I replaced the TPS issue when I had the Roadster. Also, along those same lines, be sure that you don't over tighten the TPS. It calls for a very low torque value. Just throwing that in there. In addition to the things you mentioned I'd add fuel filter and, if the original air filter system as been replaced look for cracked caps on the throttle body.
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All original air intake, I'm sure the fuel filter could use a replacement, not from miles but purely from age.

I know the bike runs well, as I've seen it, briefly.

At wide open, it's amazing. Doesn't Skip a beat. It's only at idle and low throttle
 
Just sitting here with coffee and muffin in hand watching (reading thread) the great masters at work helping/training/adviceing the rocket owners working on their machine
The knowledge and the way of explaining and their patience for the questions that they are asked is just amazing to me..
You are great and thank for all of your advice and the time spent helping the rocket owners.
 
I got a Bluetooth adapter from a friend. It's the BAF one. Itll allow reading and diagnosing.

I've attached the screenshots from it.

I did the separate diagnostic step, setting the TPS voltage and it said .601, which is well within spec. Secondary was .72

Still no codes.

Maybe something else in the pics will inspire somebody.

In the meantime I'm gonna look for vacuum leaks

Also, fwiw, the bike sat for nearly 4 hours. When I started it up, it started easily and idled fine, and even revved fine, for about 10 minutes before it went to pot.
 

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This might sound a little nuts, but have you checked the fuel pump discharge pressure? On another forum a guy with an older bike was having trouble much like yours and when he tested the pump pressure it was 10psig. Normal pressure is 43.5 psig (or 3 bar) for his application. If your internal fuel filter is clogged or the pump is not developing the required head pressure your fuel injection will be way off. Just a thought.
 
atomsplitter said:
This might sound a little nuts, but have you checked the fuel pump discharge pressure? On another forum a guy with an older bike was having trouble much like yours and when he tested the pump pressure it was 10psig. Normal pressure is 43.5 psig (or 3 bar) for his application. If your internal fuel filter is clogged or the pump is not developing the required head pressure your fuel injection will be way off. Just a thought.
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I wouldn't even know where to begin with that. I'll look in the manual and see.

It could make sense, as it seems to be fine for a few minutes when it sets for a while. It's like the fuel builds up in the filter area?
 
970hPa at 850rpm and 2.7% throttle... your MAP sensor is seeing near atmospheric pressure and causing ECU to dump fuel in as a result.
Means there is quite likely a vacuum tube or rubber cap inc connection leaking.
 
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