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Discussion Starter #1 (Edited)
Hi!

A picture tells 1000 words in a second, so please look at this video:
(It's mine :D )

Symptoms:
  • Running really rich ( smell of fuel, pure black smoke at high rpms )
  • Rpm's not falling or falling really slowly after touching accelerator
  • Rough idle
  • Don't shows any ECU error codes

What i already tried:
  • Disconnected vacuum tube from FPR - everything is dry - no signs of fuel, also almost no changes in behavior
  • Tested MAP sensor voltages: 3.06v no engine running, 2.65v idle ( Service manual tells this is OK), a higher rpms voltage falls more ( about 2.00v at 5K-6K rpms)
  • Disconnected MAP sensor - ECU goes in to failsafe mode, result:
    • Much more Stable idle, almost ideal ;)
    • Not running rich - running ok - no fuel smell ect...
    • RPM's are falling like charm
    • Display shows FI error - of course :D MAP sensor is disconnected.

My conclusions:
  • On a fixed fuel map(failsafe operation) everything works great - so i think, that this problem is not related to purely mechanical stuff.
  • Still not sure about map sensor - easy to remove & after removing bike runs smooth ( kinda psychological factor )
  • Doesn't look like a synchronization problem - should fail also in failsafe mode
  • Don't think, that this is related to broken vacuum lines or additional air sucked in though cracks or whatever - referring to normal failsafe operation.

Small note: Environmental temperature is about ~ +2C (~35.6F).

Any suggestions or what i should check next?

P.S. This may be similar to http://www.fireblades.org/forums/ar...-fast-idle-tickover-over-revving-problem.html

P.P.S. Yeah - first post as usual in wrong group - admins - please move this to general fireblades forum :huh:
 

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Nice information and video. It looks like you might have isolated your problem that being the Map Sensor. I ordered a new Map Sensor and hopefully it will fix my issue. I am going to sync the Throttle Bodies again afterwards. My problems started happening after I replaced my cylinder head.
 

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i had a real similiar problem with mine. just got mine fixed a week ago because i was riding and turned the throttle loose and the rpm stayed up like i was holdn the throttle. An when i let it idle it idled high. I had a pinched return cable. When i release the throttle the cable wasnt allowing the throttle to go back to normal position becuase the cable was pinched
 

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sorry to tell this to u bro but it might be ur fuel injectors. I had the same problem two weeks ago. Ran up to get my bike dianosed, Spell check< and thats wut it was. who would have known?:cool: Check around just in case
 

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sorry to tell this to u bro but it might be ur fuel injectors. I had the same problem two weeks ago. Ran up to get my bike dianosed, Spell check< and thats wut it was. who would have known?:cool: Check around just in case
seems weird that the revs don't stick when the Map is unpluged. Charles, did you have the injectors cleaned and balanced or did you end up buying a new set?
 

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With the MAP unplugged it makes sense that it wouldnt stick the revs...

When the ECU goes into fail safe, it should be running rich.. So I am not to sure on the MAP being at full fault for this.
 

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Discussion Starter #9
Went today to shop/garage and had a small chit-chat with some local gurus. They pointed to TPS(Throttle Position Sensor).

So TPS reports, that Throttle is open more than actual - so ECU keeps injectors longer to add more fuel. This can explain why it goes really rich. Will check TPS on saturday ( It's off season on my side now).
 

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Went today to shop/garage and had a small chit-chat with some local gurus. They pointed to TPS(Throttle Position Sensor).

So TPS reports, that Throttle is open more than actual - so ECU keeps injectors longer to add more fuel. This can explain why it goes really rich. Will check TPS on saturday ( It's off season on my side now).

That is the second TPS issue i heard of this week. is this something that goes out all the time with the 929?:idunno:
 

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Samofals, was the bike exhibiting these symptoms when you got it or do you know what happened leading up to the problem? Have you just done some other work to it...?
 

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Discussion Starter #12
Samofals, was the bike exhibiting these symptoms when you got it or do you know what happened leading up to the problem? Have you just done some other work to it...?
The bike was exhibiting these symptoms when I got it - so now I have a beautiful puzzle :huh:
 

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Discussion Starter #13
Tried to check TPS on sunday - omg, it's right beneath the frame ( on the right side of throttle body ) - how to access it ? It's even really hard to access wiring on TPS sensor.

Do i need to remove engine 4screws & lower engine slowly (Fuel tank, and airbox already removed) ? Or there is another way how to access this TPS normally?
 

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Does engine temperature make any difference to the symptoms - I couldn't see the temp gauge in your vid to know if the bike was already warm at the beginning...?

I can't see that anything mechanical like a pinched cable would be at fault as this would not be affected by unplugging sensors.

Don't understand the failsafe mode bit.....

Can you beg/steal/borrow another MAP sensor so you can rule that out? As ever, start with the easy stuff!
 

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If this is a 'racing tickover' problem on cold start on a bike with auto choke, I did post a possible solution on here about 2 years ago now.

If you search on '929 cold start tickover problem' it will probably appear...

Not been on here in ages so probably lots of other good stuff on the subject been written since then!

Cheers,

Bob.
 
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