Monster 796 - Idle issue

[andressandoval]

So after owning my Monster 796 for a year and a half, and 4,400 miles, last week I started experiencing some problems with beloved bike.

For some odd reason, it can't keep itself on while on idle, once it goes under 1,500 rpm's it just stalls and dies. No engine light and no error message. Once you start riding, everything is ok, that is until the bike is on idle again, when it will die on me again.

It does not matter if the bike is cold, warm or hot, it still does it.

I took it to my Ducati dealer, and after spending a few hours there, they could not figure out what was wrong with it. They checked air filter, fuel, spark plugs, plugged it to the computer, reset it, etc., still nothing changed.

I took it home today, and I'm supposed to take it back to them on Tuesday, to see if they can crack this mistery.

FYI, the bike has not been modified, no aftermarket parts, no performance upgrades, 100% original.

Has anyone experienced this? Or does anyone have an idea of what might be wrong with my bike?

Thanks

[Curmudgeon]

Your bike is like a modern car and that idle is maintained by the ECU. I'd guess that somewhere the ECU is getting an erroneous reading, caused by a bad sensor or chafed wire. All those sensor parameters show up on the computer the dealer has. That's where they have to start and they need to get DNA on the phone if they can't interpret those readings. IMO checking the air filter and plugs was a waste of time. That ECU can maintain 1200 RPM as operating parameters change. You know this. Why they don't is a bit scary.

Good luck and keep us posted!

[ungeheuer]

Idle stepper motor?

[Curmudgeon]

Idle stepper motor?

Absolutely! Might be the symptom rather than the root cause though. Should show up in the hand tester readings, no?

[aaen]

Mine did the exact samething when i first got it. No explanation, it just stopped after a few days. Had it checked out nothing is wrong. I'd be interested in knowing the answer though. She works amazing right now, but i was curious as to why it was happening myself.

[Duc796canada]

Something about resetting the TPS.

[Curmudgeon]

Something about resetting the TPS.

That I doubt, but you can do that manually by slowly cycling the ignition three times on the new bikes. Will bet $0.05 it does zip however. 

[thought]

I was going to suggest resetting the tps till I read that he already took it to the dealer... I figured they would have tried it out

[Curmudgeon]

I was going to suggest resetting the tps till I read that he already took it to the dealer... I figured they would have tried it out

Right. They always do that when they plug in the Ducati "testbooK" as a matter of course. I watched Donnie when he did my service and checked all the parameters as the O2 sensors got hot enough to come online. Must be 30 - 40 readings you get from that screen in real time.

[andressandoval]

Yes, I forgot to mention, resetting the TPS was one of the things they tried, didn't work.

So, the bike is at the dealer and I asked them to PLEASE DO NOT CALL until you have this resolved and you know what happened.

I'm guessing it will be a while.

Thanks to all of you for putting your two cents, it helps a lot.

[andressandoval]

Got the call from the dealer today.

The root of the problem turned out to be a cracked vacuum line coming out of the throttle.

Problem solved and covered under warranty.

Will pick up tomorrow morning.

Thanks everyone for your help and comments.

[Curmudgeon]

Got the call from the dealer today.

The root of the problem turned out to be a cracked vacuum line coming out of the throttle.

Problem solved and covered under warranty.

Will pick up tomorrow morning.

Thanks everyone for your help and comments.

Filed away for future reference. Figured it would be something like that. Guess they put their glasses on this time when they checked all the readings.