Modern Vespa

Hello All,

I'm wondering if there are any 946 owners out there that have same problem as I have with my 946, it stalls when you accelerate from a stop, it has only happened twice since I had the bike (about 900km on the clock), both of time engine was running at riding temperature.

Dealer can't figure out what cause the problem as they will need to "see" the stall before they can try to figure it out what cause the stall.

Any thoughts?

Thanks in Advance!

It happened to me once just before my first 1000km service. Was very spluttery during the first 1000 when starting cold. Not so much now that
I've changed the oil and remus pipe and it never happened since. Great on start up and off the line.
The bike just feels quicker and more responsive as you put on the kilometres.

Does this "dealer" have the Piaggio diagnostic equipment so he can check for codes generated by engine malfunctions? If not, find a different dealer.

I agree with Dooglas. I wonder if maybe some of the 946s have the same issue some of the BV350s had; a bad HT Lead.

Hello Dooglas,

They do have the diagnostic equipment and there was no code found. Unfortunately I'm in Hong Kong and there is only one authorized Vespa dealer here.

Thank you Dooglas and all!

Might have something for you.
The exhaust sensor seems to be failing quite easy and a symptom is stalling.
http://www.scooterwest.com/items/?_pageCCS=t#page=/item_details/Oxygen-Sensor-Vespa-946/10699

Hope that helps.

Thanks I'll look into it!

I've experienced 1 stall in just under 300 miles of ownership. I was sitting at a red light - blipped the throttle a little bit to move forward - and it stalled. Fired right back up, and it hasn't happened since...

Since this is something others have reported, I'll keep up with this thread to see if we can find a more clear pattern. Otherwise, this machine is 100% *perfect*!

I had the exact thing as masala with my 3v engine.

Over 6k km's now and hasn't stalled since, so I just put it down to a little hiccup during breaking in the engine.

Happened again today to me... I'd been out on a 20-ish mile long ride, just around town, and I came to the last red light before my neighborhood. I sat there for 30 seconds or so, waiting for the light to change, and when it turned green, the 946 stalled when I rolled on the throttle. Fortunately, the flatbed tow-truck behind me didn't run me over, but instead applied his brakes and waited for me to restart my bike.

As usual, smooth sailing since then...

Random.

Is it a coincidence that this also happened to me with my new 2015 Primavera? This better be a blip and part of engine break in. I had filled up with fuel 10 minutes earlier.

Had a 2012 Yamaha BWS 50 and it never, ever stalled. I hope this is not a Vespa quality issue but am grateful for the 2 year warranty if it is.

my GTS would stall on idle.....problem fixed with a remap. Scary that your 946 stalls on acceleration, that is a whole lot more scary. Good luck, hope its sorted soon.

It happened once to me too. I also experienced mild hesitations when i started moving. It happened before the odometer showed 500 mi.
I found out that if I warm the engine up for just few minutes it doesn't happen at all, neither hesitation nor stalling.

No stall for me through almost 400 miles.

Glad it's only happened to you once, but for me, the problem is most definitely not warming up the bike. Mine typically happens after a period of idling once the bike is fully warm (i.e., sitting at a red light) and has been ridden for a while.

Maybe it is time to go to a dealer for the first scheduled maintenance? A little earlier but for a good reason.

I got 600. It is time to schedule a visit to a pediatrician I'll have to haul her for 3-4 h. So far, she is resting in the garage while PX works, with a little help of mama Primavera

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Any updates on this?

Wouldn't this problem throw a code?

Just got my 946 back from the dealer last week and the stalling problem is solved! No more arching which was stalling it out. It's now serviced and awaiting for some fun miles ahead

I'd say the answer to that is yes.