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Hey guys!

I've got a problem with my F3 800 (MY2014). After 5800 kilometres I got a fault popup on my cockpit.

"Malfunction Exhaust Valve"

I drove to my dealer. He started the self-learning procedure and everything looked fine.. but just for 5km. 5km later I got the same fault. I drove back and he told me that he has to check the whole exhaust valve system to find a solution. Well, sounds logically to me. But I won't get a date for this inspection arranged as fast as I'd like.

So, I drove back at home and checked the exhaust system by myself. For me it looks like that the cable which openes the exhaust valve has to much loose.

Is anyone able to explain in good technical english what I should do to adjust it properly, so that I could do it by myself?

After that I would drive to my dealer to do the self-learning procedure once again, so that the ECU can determine the limits.

Regards,
Jarosch
 

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hi Jarosch, the exhaust valve works by a cable looped around the servo with each end of the cable fixed in slots on the exhaust valve , to have slack in the cable i suggest that either one end has come out of the mechanical valve or the loop around the servo is in some way at fault, hope this can throw some light on your problem
 

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Make sure you check both cables. I have had an issue when a small stone got caught in the groove on the pulley, making the cable tight and holding the valve open.
 

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Old Wing Nut
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Cable adjustment (and simple inspection) on exhaust valve is routine maintenance.
The actuator has a sensor inside that tells the ECM where the valve is in its movement by variable resistance (voltage). It gets a 5 volt supply from the system and senses voltage drop on the center tap of the variable resistance. Typically a fully open valve would read 4.1 or more volts and a fully closed valve around 0.9 volts.

The cables usually work against a spring load on the valve that will open it fully as default if a cable breaks or is disconnected. So even though there is a push-pull cable set-up, they are both essentially working to control a spring loaded valve meaning only one cable is in constant tension.

Haven't read up on the MV adjustment procedure, but the valve probably cycles fully open and close as a system test when the key is turned on....so you could back probe the sensor wires and see what the voltages read.

But a big disclaimer here.....all my practical experience is based on the Japanese EFI systems here. Maybe MV and Aprillia etc use somethin totally different?
 
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