Modern Vespa

Last weekend we took advantage of the warm weather and went out for about a 4 hour ride. My MP3 performed perfectly (I even got up to 70 mph at one point, but that's another story!)

However at the end of the ride, when I slowed way down to make the turn into my driveway, the engine stalled just before the front wheels bumped up the curb. Luckily I had enough momentum to get all the wheels up the curb and I didn't drop. I didn't see any warning lights on, the run switch was still on, nothing seemed amiss, so I hit the ignition. It started normally and I continued up the driveway and into the garage. It had plenty of gas in the tank.

Anything I should worry about?

Can you find out if the fuel pump was replaced under the recall? My 250 was covered, but I'm not sure about the 400.

Thanks! I will ask my guys at Renegade.

Not aware of a fuel pump recall on 400s.

When you are off the throttle and slow below around 10 mph the clutch disengages and the engine is at idle.

Have you had the ECU update? You can find a few threads here about stalling when off the throttle slowing down and many who say the problem was fixed with ECU update.

Also some have had problems with kill switch. This more often happens as speed, not specifically related to slowing down. If you haven't done dielectric grease treatment of switches this can be a problem. Search for threads on the grease.

A couple had the problems at idle with extra washer either thicker than the ones BubaJon has or combined with non-stock variator.

If your evap canister or roll over valve is not functioning properly there can be a vacumn in the gas tank to cause a problem. Many of us have removed both. If yours is bad you can have either problems removing the gas cap from vacumn or hear air escaping from pressure when removing gas cap. In at least one extreme case somone reported the gas cap flying past them when removing it from lots of over pressure.

Ch air filter, is it clean?

While you have it off run some carburator cleaner through the intake.

I useds Deep creep sea foam {aerosol can} through mine and it stopped doing what yours is doing.

throttle body cleaner , not carb cleaner.

That happpened to me once on my 500.. it just died.. and then started normally.. checked trouble codes.. nothing.. I figured it was just....a..glitch..

I had the same thing happen a couple of weeks ago. Went for a ride around town to run errands, drove for about a half an hour then turned it off for a ten minute stop. Started it up normally drove under 30 mph for a block, pulled up to a stop sign and she died. Everything read normal, so I turned everything off and re-started, I haven't had a problem since. All the fluids were good (including gas) and the battery terminals were tight. I don't what the deal was, guess the scoot just need a little breather.

i have had this issue with my 'funky' slowing down to a stop an at low rpm the engine would die. i just come to a stop, turn off the key, wait a few seconds, like count to twenty, then restart and i may never have it die on me again.
when i fill up i put in sea foam and something to clean the jets, then i may not experience it again until i get low on fuel before i fill up.

Not meaning to be funny, but could you have inadvertently bumped the Kill Switch?

I think that a gas additive does not clean the throttle body idle bypass tube. To clean that you have to remove the air cleaner and the hose going to the throttle body and then spray throttle body cleaner directly into the bypass tube while running the engine.

I'm sure wiser heads will add their thoughts.

That is correct.

Mine does this occasionally too. Usually it is in cold weather. No ECU update yet.

Thanks OAD. You are correct!

Fixed that for you...

Now that FM mentioned Sea Foam, mine died after putting Sea Foam in the gas. Is it possible the mp3's don't like Sea Foam in the fuel? I didn't put any SeaFoam in subsequent fill ups and haven't had it die again. I guess I'll try YaYaDave's advice and clean the throttle body with the aerosol Sea Foam.

Using Sea Foam in mine per recommendation from previous owner and the local service department. No stalls yet.