Modern Vespa

As I mentioned in another thread I just picked up a 2008 Sportcity 250 with 1200 miles on it and I am loving the bike - for the most part....

...it had started stalling on me. Of course it did not happen on the test ride! It seems to be happening once the bike is fully warmed up and only when there is no throttle at all. It restarts immediatley when you press the starter - but it is a little worrisome when it happens at a noisy intersection and you have not heard that the engine has died....

The usual suspects:

1. Dreaded Evap System? (but it seems to restart without any problem unlike the evap/vacuum problem)
2. Loose Spark plug wire (doubtful since it restarts so quickly)
3. Idle adjustment too low (? maybe since even the slightest throttle will prevent it from stalling)
4. Bad/old gas?


I am really nervous that I bought a lemon or something. I have called the previous owner and he is not getting back to me - of course.... great what did I just buy? Help me feel better about this purchace.

I posted over at af1racing too - but since this is the same drivetrain as the GTS, I assume the lessons learned from the other 250ie owners may apply here.

I am searching the wiki as we speak - but have not found an idential issue/symptom yet.

Thanks for any help.

For bad gas try some sea-foam or stabil. As for the idle, I think the 2008's have fuel injection, so that's probably not the problem. It should be idling at 1,650 rpm. If it's off you need the dealer to adjust it's computer module (not a DIY job).

Another thought, you could reset the cpu by disconnecting the battery for 10-15 min. Then it will readjust or 'relearn' it's run settings.


Good luck with it!


Regards
Harvey

On mine, the gas line from the fuel pump to the EFI/carb was improperly connected at pump. I had put quite a few miles on it before it worked its way loose. This doesn't exactly sound like your problem, but I dunno, perhaps when the injection system (pump, lines, carb, tank) isn't quite right momentary loss of pressure could cause stalling.

If this is your problem, you will eventually know it because when the hose does come off completely it will leak gas. Its a simple fix -- only a snap connector -- but there is a lot of plastic in the way.

Run it again and when it stalls, take the gas cap off and see if you hear a whooshing sound. If you do, pressure is building up due to the Evap Canister.
You can disconnect the evap system by cutting two hoses. Cut the hose from the gas overflow line that comes off of the side of the gas filler under the gas cap: add an extension to the line and run it towards the ground for overflowed gas.
The other hose to cut is the one going to the throttle body from the canister. Take the open hose end that you cut (the side going to the throttle body) and plug it with a bolt that fits tightly and a worm clamp to make sure the bolt won't work loose.
You can leave everything else where it is since it's disconnected after cutting the two hoses.

Hmm, could be. I now doubt it is the evap - I definitely do not get the "whoosh" when opening the tank, plus it restarts right away. One other possible culprit is the fact that I now know the previous owner did not take to the dealer for the 600 mile /1000km first service. He did the hub oil and engine oil change himself since the dealer was 60 miles away from him. I'm wondering if I need to take it in and maybe see if there is a CDI reflash/update? I will try the ecu reset tonight by disconnecting the battery. Vespa/Aprillia Philly is not too far away from me.

It has to be fuel delivery related since the slightest bit of throttle will prevent it from happening...but only fuel delivery at idle. The thing performs great in general with no stumbling/stalling - in fact, it pulls great at WOT

FI bikes don't have idle adjustments, and don't get the same evap problems as the carbed bikes do. The first thing I'd check is the fuel pressure. If the spark plug is good, which it should be with that low mileage, I'd think fuel pressure is the likely candidate. Do you hear a buzz he you turn the key on? (before hitting the start button). If it's weak or sometimes absent, you'll need to check the fuel pump and its relay/wiring. If you have one, put a fuel pressure guage on the line and see what you get when you turn the key on.

Sounds like an idle problem Unless the throttle cable is REALLY loose, it's most likely software related. Disconnecting the battery for a while to reset is a good idea. If that doesn't do it, the dealer can find it quickly with a diagnostic tool.
Hope it gets fixed fast.

Thanks for all of the ideas. I just got back from a ride and it seems to be happening a lot more - almost every time I stop unless I keep on the trottle a little bit. I did think I noticed it backfiring (popping is more like it) a bit just now on throttle off - related?

I do hear the buzz of the fuel pump when I tun the key. It is very audible, but onyl lasts for 1-2 seconds (I assume enough to pressurize the system?)....or should it stay buzzing? I do not have a fuel gage - so I may just take it to the local dealer for a once over.

One thing I did notice is that the acutal throttle grip seems to have about 1/8 turn of travel before it engages the throttle cable. I assume that since this is a FI engine the physical "looseness" of the throttle cable should not affect the idle at all - the computer is taking care of that.

Try a gas treatment as well see this thread (from a dealer):
FYI - Scooterist with rough idle and stalling issues.
You could also check your spark plug wire, as well.
The slightly losse throttle is normal.

Good luck!


Regards
Harvey

drew wrote +1

I would agree that the evap system has no effect on the fuel injected vehicle as the O2 sensor makes all the corrections. Also disconnecting the battery or the ECU will not reset the ECU only the scanner tool can do this. Best talk it to the dealer as they will have everything to look into the running issue.

Jon

You may want to try having your dealer reset the throttle position sensor with the diagnostic computer.

Thanks, that sounds reasonable and describes the symtoms well.

I did, just in case, ad some fuel treatment this AM and plan to run the tank down close to empty ASAP...my impression is that the bike was sitting a while before I bought it - who knows how old the gas is in there (we also run 10% ethanol around here - and I know that can cause issues when sitting). In my experience though bad gas causes hiccups and stalling throughout the rev range and in fact (at least in my car) gets way worse at WOT. That is not the case there - the bike has plenty of power once you begin moving. I am not sure how the FI works here (Mass-air flow, O2 sensors, etc.)... maybe h20 in the gas would cause the stall only at idle - but I doubt it.

I also plan on checking the spark plug tonight.

I have an appointment set up with Zespa/Aprillia Philly already. Thanks for all of the assistance - I will keep you all updated. Grazie!!

-John

Start with disconnecting the battery. My scoot started stalling constantly at about 3500 miles, running rough, popping, etc. Ten minutes after disconnecting the battery, all was perfect again and I haven't looked back.

What is the battery gauge telling you? You can use the mode button (right side) to see what the current battery charge is.

I had a similar problem that eventually turned into difficulty starting up and then a dead sportcity. A new battery, and it's been perfect ever since. As it's fuel injected, if there isn't enough charge while it's idling then it just won't work.

Get the battery checked out, I'd say.

You should bring it to an Aprilia dealer. They can hook it up to the computer program that can quickly and easily diagnose the problem. I was having a similar problem on one of my bikes and they were able to tune the bike quickly with not much fuss.

Tell Jon at Vespa Philly service dept that Drew says hi.

I think I make have solved it....

Took off the "right inspection panel" and barely touched the spark plug wire only to have it fully separate from the boot. I have to say was pretty excited to find out it was something so simple.

Now, on to the fix...

...It looks like the wire is attached to the boot basically by screwing the boot up into the stranded wire of the cable. I was surprised how far I could thread the boot back up into the wire core. My guess it that it is temporary and I'll need a new spark plug wire eventually.

I remembered reading about this problem in a review of the Sportcity in this review:

http://motorcycles.about.com/b/2008/03/07/full-review-2008-aprilia-sportcity-250-scooter.htm

I seems that at least in the Sportcity's case the cable is too short and works itself loose since the motor is always moving (on the swingarm) and the other end of the cable is fixed to the coil on the frame. It seems to me that the cable needs to be about 1 inch longer.

Can I just fabricate my own cable? I might call the dealer to see if this might be a hidden warranty/recall item.

I just got back from a ride - it runs great!!



whew.

Now off to go see some fireworks...

Happy 4th everyone!