Benelli Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
784 Posts
Discussion Starter · #1 ·
Local dealer says he is going to change out the IACV (idle air control valve) stepper motor. I have read a few threads on this before. But it also seems that it could be a combination of things. "CO setting, could be throttle body balance,TPS, IACV"

One more thing, if the IACV is found to be faulty what else has to be done when you replace the IACV?

We will see this coming week. I will post the outcome later.
 

·
Registered
Joined
·
78 Posts
As I understand it the IACV is a known fault. Ive just had mine changed due to stalling and while its certainly running smoother it hasnt rectified the issue so its headed back for more diagnosis. With that said however, Ive spoken to two other owners who have had the IACV changed (and the bike retuned) and have had no further issues.

Id say theres more than one cause in the TNT for the low rpm stalling but the IACV seems to be accepted as one.
 

·
Registered
Joined
·
209 Posts
Hi,

The air idle valve is a new one on me, I'll have to get mine checked. But other issues that can cause stalling are water in the coils, back firing through the inlet ports and mapping issues.

ciao
Derek
 

·
Registered
Joined
·
209 Posts
Oops silly me. I forgot the IACV is the stepper. Yes mines been done .... twice :) :doh: :doh:
 

·
Registered
Joined
·
376 Posts
99% of stalling and idle variation issues are incorrect setup. I know, been there done that :doh:

Typically, if the air bypass stepper is faulty, the bike runs very rich when warm and fouls the plugs. What happens is the plunger comes off the actuating rod and stays in the warmup position. Replacement steppers are improved and shouldn't have this issue.

However, it is worth changing the plugs & checking the stick coils, either can cause misfires. Been there too :p

Mike
 

·
Registered
Joined
·
784 Posts
Discussion Starter · #6 · (Edited)
Dealer says lets try this instead...

I figured that the bike has been setup incorrectly. But my dealer insists that it is the IACV and probably a bad map.:mad:

I have no other choice right now but wait for the IACV.:bawl:

I have noticed the bike stalls more once it gets warmed up.

What steps do I need to take to setup the bike.:confused: Service manual page numbers would help.

Do I need any special equipment?
 

·
Registered
Joined
·
346 Posts
Dude, I feel for you man. You're a champion of patience, because I would have been pushing for a new bike by now. It's strange how some have problems and some don't. I ride my bike pretty hard, but don't seem be having any issues (only 2500 miles or so). Others haven't had any problems either, but some have nothing but problems. Benelli really needs to get this worked out a little better if they're planning to compete in a market with top performing reliable jap bikes. I mean, one day the japs are going to get it right and start putting more effort into the fit and finish and the small details on their bikes and when that day comes the italian bike companies won't stand a chance.
Well, I hope they get your issues resolved soon. Best of luck to you!
 

·
Registered
Joined
·
784 Posts
Discussion Starter · #10 · (Edited)
Still waiting for the IACV, dealer says it is on backorder:mad: Haven't had the nerve to ride the bike in this condition. I am getting withdraw symptoms; it’s already been 2 months the bike has been down. I felt so shitty today I took out the ole Buell and rode the crap out of it.
 

·
I'm firing on three
Joined
·
611 Posts
Remind me, have you removed the exhaust valve or modified the airbox yet?

Only IMHO your problem sounds 100% like fuelling......normally if the engine is running weak at the bottom end it will be erratic at idle speed, or as you shut the throttle off when you reach a junction and come to a halt it stalls.
Whilst these engines are all guilty of running way to rich at the mid and high end it’s not uncommon for them to have a weak spot at the very bottom end
there is another quirk with the Benelli set up concerning the exhaust and airbox valves, as we know at about 3500ish rpm they are both supposed to open, and the same applies in reverse as we slow down and the revs decrease the valves are supposed to close…..problem is there are 2 cables running to the solenoid valve (1 to the exhaust and 1 to the airbox) after a few dusty miles (obviously not in the UK) or a large amount of British weather the solenoid valve and cables get gritty and start to struggle, meaning it doesn’t close properly when slowing down or worst it doesn’t open properly when reaching 3500rpm (only pulled open by the coil spring on the exhaust and the tiny springs on the airbox flaps) this inconsistency can play havoc with the fuelling particularly at idle speeds.
You could richen up the mixture by adjusting the air bypass screws yourself if you felt confident, or get you dealer to put a C0 meter on and adjust while the engine is running.
Best of luck whatever way you decide to go…….I hope you get it sorted soon before Benelli destroys all of your enthusiasm and patience.
 

·
I'm firing on three
Joined
·
611 Posts
with the filter out start the engine and look at the flaps in the airbox if you blip the throttle to say 4000rpm do they flick straight open or do they flicker open and closed (sluggish)? if you dont want to mod the airbox yet try cable tying them open and run with filter in (to prevent the tie sucking into your engine if it did slip off) and see if there is any difference even if slight.
personally I think your dealer needs to set up the C0's and not play around with the stepper.
Terry
 
1 - 13 of 13 Posts
Top