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Discussion Starter · #1 ·
Sorry for the misplaced post, but I just got a 996 and I’m trying to get running smooth. The forums aren’t allowing me to post in tech for some reason so here I am.

The issues I’m having are:
Will sometimes stall when cold
Will lose power around 5k RPM (most noticeable in first gear)
Will sometimes not start at all, fuel will prime and motor will crank fine but won’t start. This usually happens after the bike is already warm.

Here’s the tricky part. I originally thought oh it’s just the fuel filter, but last time I got stranded and the bike wouldn’t start I had it jump started by a guy driving by. Started up INSTANTLY. BUT I just had my battery checked at the local battery shop and they said it’s doing great. However that was after I had the battery on a tender overnight, so right now I’m going to check the voltage while the bike is running.

Could this be a stator/rectifier or something electrical that would cause these symptoms? All electrical connections seemed ok, there is a yellow plug under the seat with no female connector, not sure where it goes. Also the breather tube under the gas tank that usually goes to a Y-connector isn’t connected to anything. Keep in mind I’ve had my battery on a tender so it’s possible that the stator isn’t charging it but I am. Also, the bike had died at idle after charging overnight too.

Sorry for the mess of info but if anyone can help that’d be super appreciated, just trying to get back on the road!
 

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The charging system must be checked out. Check the wires (yellow) going to and from the rectifier. They are likely scorched, or the connector is. At 4k RPM you need to see 13.2 or so volts. A flat 12.5 at idle isn't a good sign, but it is not a bad one. The stumble sounds like a power issue (voltage) or bad fuel lines in the tank. More likely a voltage problem. If you aren't getting a proper charge but the battery is fully charged, then you can get around 30 miles before it starts giving you issues.

Those connectors in the picture are more than likely from the injectors. The 996 has 4, but we typically fix that down to 2. A very common mod is the change out the EEPROM/chip in the ECU for a setup that only uses 1 injector in each throttle body. With those ECUs installed you remove one of the connections to the injectors on each cylinder. It doesn't matter which one.
 

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Hi and welcome to the Ducati List! Please place your location and what year & model Duc are in your barn. From the frame color, yours is a '99 if its a 996.

A few thoughts:
Best 996 starting technique - this engine likes no throttle when starting, until she just begins to light, only then EASE in a VERY slight bit of throttle til she's idling. If that doesn't do it regularly, she's out of tune or poor spark may be present.
If she stalls when cold, or hot, she's out of tune or poor spark may be present.
Battery running at less than 13v, with engine running is too low.
If you jumped your bike from a car, the regulator's likely now fully cooked. See Look forward to a stranding when the battery runs out of juice.
Send pix of that connection further out so we can see what's around it. It looks like a coolant temp sensor or fuel injector connection. If the former, re-connect it! If the latter, this may be OK, since one of the hot setups for the 996 was a single injector setup, and in this usage, one injector wire is just disconnected. It should have been wrapped or terminated properly however, to keep it out of the weather.

Search this Forum. Everything you are looking for is already posted up here, long ago.


Best,
 
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Ahh, I see Namor was typing at the same time.. you're in good hands there! Do note the starting technique I mentioned. the 996 Desmoquattro engine starting is persnickety that way!
 
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Rectifier wires and connector (inside) look good
Do check the output, resistance and conductance. There's a cat on Youtube does a good video if this procedure.
 

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Discussion Starter · #10 ·
Yea that’s how I’ve been starting her per advice of some WERA guys. It’s only if I don’t give that little 1500 RPM ounce of throttle after about 10 seconds that she’ll stall. Just has to be a crack and she’s fine for the rest of the ride.
 

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Hi and welcome to Ducati.ms. Super glad to have you roaming our halls.

Please fill in your location information in the UserCP Edit Your Details section, that can help if there might be someone local to you give a hand or find new friends to take a ride.
 

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Discussion Starter · #13 ·
Well it’s definitely electrical. Was running perfect after fully charging the battery. After sitting for a few hours at my buddies place it hardly started. I then rode home on one cylinder. Won’t be riding again until it’s fixed. I’m swamped with summer classes right now so it may be next week until I can diagnose it. It’s either a bad ground, charging, or the battery itself I’m guessing. Battery store said the battery was fine but that was after charging it all night so who knows maybe it was just ok because I’d just charged it.

I suppose next step is testing the stator, rectifier, etc. as suggested. Or is there a way that I can ACTUALLY check the battery and know exactly whether it’s ok or not?
 

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Discussion Starter · #14 ·
Just did a test checking the amperage when I disconnect the positive terminal and do an amperage test between the positive wire and the positive terminal. Came out to be .7mA. So that tells me something is draining the battery when it sits. Now I’ll try to find the best way to locate the source.
 

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Discussion Starter · #15 ·
Actually .7mA may be within specification now that I think of it. Should have paid attention in my circuits class. I’ll do some research before making any more conclusions.
 

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Discussion Starter · #16 ·
Could shotty turn signal connections cause this? All of my signals work but they are sort of make-shift connections where I compacted larger connectors to fit into the female connectors. Maybe could this hinder current flow to the charging system?

Also the turn signals blink twice slow and then very fast. I’m now piecing it together that this could be flagging an issue. I’m going to buy some legit connectors at the auto store today and rewire them. It needs to be done regardless of whether it’s the problem.
 

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You should have no problem posting in the Tech or Bike specific forums to get more exposure to answers to your questions, the reason you could not do it at first is because you had to post a welcome thread here to get started and approved.
 
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