Bad Idle and won't stay on (but turn on...)

[Mihalis fjr]

I don't believe that the problem comes from the fuel pump.I have never heard for a defective fjr's fuel pump.

The odd is that you leave your bike in the garage for six months without to do anything and after that the problem is here...

 

[lele]

now I have discovered that the new spark plugs are full of black carbon.

is this a symptom of bad carburation?

 

[rushes]

I might check the air filter again, and also look in the exhaust.

I had a mouse fill a muffler with dog food once.

 

[lele]

Tomorrow I will check the o2 sensor-wire

 

[Mihalis fjr]

Full of black carbon mean very rich mixture.So no problem with fuel,fuel pump,etc...
Perhaps the throttle bodies for a reason they are clogged in the air circuit.If the problem is there,you could unscrew the four air mixture screws,i mean the four screws where you use to do the synchronisation,and blow some compressed air in the four holes.Every screw accompanied with a spring,washer,and a small oring.If you do this job,be careful to not loose these things.Also after that you must do a syncronisation on the throttle bodies.Not sure if the problem is there,only a thought.
The o2 sensor or a defective wire i don't believe that it could cause this problem.

 

[RaYzerman19]

Have you seen any error codes or gone into diagnostics to see if there are any?

 

[audiowize]

It would be cheap enough to replace the plugs, just in case. I have dealt with ignition misfires, and I personally don't think you have one. The advice about checking the exhaust and air intake for obstructions is good. I would be most suspicious of an injector clog.

 

[Mihalis fjr]

It would be cheap enough to replace the plugs, just in case. I have dealt with ignition misfires, and I personally don't think you have one. The advice about checking the exhaust and air intake for obstructions is good. I would be most suspicious of an injector clog.

lele told that he cleaned the injectors..

Also he installed new spark plugs..

In the video sounds like something is out of timing there,as the injectors,or spark not in the right time..

If the air circuits in the throttle bodies are not clogged,i don't know if a problem in the start up circuit in the plungers ''stayed in the open position''could cause a like this symptom..?!

The thriller continues...

 

[lele]

Thank u all for the support

I REALLY APPRECIATE THIS

• air filter is not clogged (the problem persist whitout it)
• injectors are clean
• plugs have been changed few days ago and had become black of carbon sign of a too rich fuel mixture ( infact there is some smoke from the mufflers)
• timing is perfect, both cams are aligned
• O2 sensor is ok
• pressure sensor is ok (it read 760mm of HG)

I m starting to think about some ECU problem, it don't send right message or read wrongs....

Have you seen any error codes or gone into diagnostics to see if there are any?

no nothing

 

[lele]

It's run like CHOKE is always OPEN

 

[lele]

If the air circuits in the throttle bodies are not clogged,i don't know if a problem in the start up circuit in the plungers ''stayed in the open position''could cause a like this symptom..?!

is this linked with the cooling system?

the hose from cooling pipe to throttle bodies provide some kind of vacuum?

maybe there is some air or bubble in that

 

[Queensland Ken]

There is a cold/fast idle mechanism behind and under the throttle bodies.

A wax motor is feed by the coolant system, wax heats up and pushes a plunger that closes off the 4 fast idle valves.

If there is air in that system, the bike can stall out, crap cold idle.

There is a good writeup with pictures on this forum.

 

[Mihalis fjr]

lele,yes they are linked with the coolant system,Have a look at these choke valves,you can see them under of the throttle bodies,at the left side of the throttle bodie.Have a look if these valves are in open or close position.Normaly when the engine is cold they should be in open position,after that,they should be in close position.You can see very easy the left valve in the left bodie..Check it.I believe that the ECU hasn't problem.You leave your bike for six months and after that the problem started..Something happened at this time,i don't know what but why the ECU..?!

 

[Donal]

Some information here here and here on the "wax motor" that controls cold idle........

 

[lele]

thank u all, today I had reassemble the head cover (need 8 new bolts, the olds are in very bad condition)and accessory on the top

tomorrow I'm going to check if that valve stay opened or close

I don't know why ECU can be broken...everything is possible, the bike got 15 years and 120000km and plus I'm very unlucky (some years ago I destroy a VTR1000 engine for the F*****G front CCT)

tomorrow I will update

 

[TomInPA]

Any chance this could be caused by a vacuum leak? Check all the vacuum caps on the throttle bodies and if you're still using the PAIR, be sure the hoses are tight and intact, especially the large one that goes to the air intake.

 

[lele]

Any chance this could be caused by a vacuum leak? Check all the vacuum caps on the throttle bodies and if you're still using the PAIR, be sure the hoses are tight and intact, especially the large one that goes to the air intake.

ok I will do it

 

[lele]

today I drain the fuel from the tank and put 10 liters of premium fuel

the engine run better but not at 100%, so I think the previus fueling was contaminated with nafta or something else

plugs still fouled, maybe keep the engine running at high rev help to clean them

 

[TomInPA]

RPMs won't matter, but it would be good to get out and ride it rather than rev it.

 

[Mihalis fjr]

As i told you in my previous post,

:

''Fill your fuel tank with 100 octanes fuel,you can find in Italy as we have in Greece,go to the autostrada,open the throttle full for as time as you can,and everything will come back to normal..!Believe me..!

Don't afraid to put the needle deep in the red zone!ut i don't know where...

But...i think the problem is somewhere else...But i don't know where...