Page 1 of 1

Idle control valve(stepper motor)

Posted: 17 Jul 2017 19:03
by MrWilson
Hey! I have had temporarily stalling problem. It's been mostly in wet conditions, but always got better sooner or later. In the same time the motor got running some kind of rough. Now it didn't cure by itself, so I opened the airbox. There was quite a lot of dirt inside. Cleaned it and oiled the air filter. But I also tried to check the idle control valve. Tune ecu says that it can't test it. I tested it by taking off the hoses. Looks that the valve is almost all the time full open. I run the motor in different rews and the valve was open all the time. Only when cutting the ignition off it shuts the valve for a while. In the same time it makes a nasty rattle voice in the middle of it's move. Tried the bike driving without the valve, just blocked the hoses. Throttle was sharper in my opinion. Idle was a little lower, but stalling was not any worse without the valve. So, should the valve be shut or open when rewwing the motor?

Re: Idle control valve(stepper motor)

Posted: 02 Aug 2021 23:55
by Will
Did you sort this out?
I've been getting a fair amount of backfiring, sometimes some coughing through the throttle bodies so I went over the exhaust and sealed it better (catalizer bracket had self-destructed so all was loose) and flashed the original map, all of which helped a lot, and tomorrow I'll see if it makes any difference putting clamps on the IAC tubes because they were pretty loose too, there could be air getting sucked through by those ginormous pistons on decel with throttle at just about nothing. Is there a way of dismantling the IAC valve to give it a proper clean out? I didn't want to break it! 2009 Scrambler ;)

Re: Idle control valve(stepper motor)

Posted: 12 Sep 2021 15:45
by augbjo2000
I have also experienced that the 9 1/2 «dont like» rain :-). It is Running very Rough and backfiring and stalling when you go off the throttle.
It must be one of the sensors ( temperature ? ) or one of the others that dont like wet conditions

It must be one that is exposed for the weather - not inside the airfilter box - I have bought a new air temp sensor - will start with that one :-)

Re: Idle control valve(stepper motor)

Posted: 14 Sep 2021 20:02
by MickeyMoto
Is the spark plug drain clear? If you check there is a hole in the head. Might be worth removing the coil and poking the hole, or even checking to see if the coil material is breaking down.

Re: Idle control valve(stepper motor)

Posted: 23 Jul 2022 09:03
by mikebn
i had a Aprlila Pegaso 650 for while it keped back fireing so i put half a can of injector cleaner in the tank and it cured it, may be worth it for a £5er

Re: Idle control valve(stepper motor)

Posted: 23 Jul 2022 16:17
by MickeyMoto
Injector cleaner follwed by an Italian Tune Up (A Tutto Gas!).