Modern Vespa

Hello again everybody. I have a big problem and I am hoping that somebody might be able to help. For some unknown reason, my MP3 is burning too much Gasoline I topped off the Tank. on the Weekend and in about 3 days of driving it is now down to a half of a Tank. Can someone please Help

Fred

Tried a new oxygen/lambda sensor?

You won't know it's the bike or the fuel gauge that's faulty until you refill and work out your mileage (or how many km per litre) - and do this at least a couple of times using the same pump.

I think, more that how many days is how much Km you do in the time and arrive to half tank? And how much liters is your tank (from your profile model looks as is 13.2 liters?)

And how do you *know* it's half full?

I've only driven it to Work and back. That`s about 60 Km Total.
It has a strong oder like it`s dumping Fuel in the Cylinder. I started it and let it run while I put my Helmet and Gloves. Then when I tried to take off, it died on me. It took me about a half an Hour to get it started again.I took the Airfilter cover off and checked the Filter and found only a little dirt around the edges.Then I tried starting it without the Cover on and it finaly started. I then put the Cover back on and let it run with a slightly higher Idle before taking off. I made it Home okay, but it still smells like it`s dumping a lot of Fuel in the Cylinder. I`m hoping that it`s nothing too Serious and that is easy to repare. I apreciate your input Gents.

Fred

It shows about Half a Tank jimc. Like I said, I topped it off and I mean all the way to the top.
So it`s actually a bit more than Half a Tank.

Fred

Pull the spark plug for inspection. That's the only real way to determine if it is really "running rich"

As you say you smell fuel and it died on you (cold, so the oxygen sensor is not used by the ecu), maybe you have something more and not only a feel that something is not good.

Pull the spark plug to see if too rich, the next is check the injector, maybe is dropping and if is, solve fast as is something not good as you can have a hidro locking in the cylinder, and this is something you don't like to have $$$$

Okay. Will do and thanks for the tips Guys. I`ll take a look and let you know what I find.

Fred

how many miles on it?

what service has been done and at what mileage?

It has almost 20k on it. The last service that was done,Idid myself. And that was an Oil change with Oilfilter, Sparkplugs, Air filter, Belt, Weights, Sliders and Pulley. That was about three Weeks ago. Is there a possibility that it could be sucking air where it shouldn't be. I had a hell of a time trying to get it to start up again and if it is sucking air could there also be a possibility that the ECU is trying to raise the mixture to compensate for the loss of vacuum?

Sounds like unmetered air to me.

Check the seal around the airbox and the clamps from the airbox to intake manifold.

And are you using the correct NGK plugs?

The Plugs are the right ones. Thanks for the tip with the Air box. I'll take a look. If it is just a loose clamp or a bad seal or something as simple as that, I'll be a very greatful and happy Pappy!

This airfilter, was it a new preoiled Piaggio filter or did you wash, clean, dry and reoil the old foam filter?

If you oversaturated the foam element with filter oil it could cause similar symptoms

The foam filter should only have a light tacky coat of filter oil sprayed on

I have one of those Molassi Sportfilters. I sprayed around the edges where the Box comes together while the Motor was running and it died on me. Then I checked the Airbox Gasket to see if it was damaged and found it missing, so I ordered a new one. I hope to recieve it sometime next Week. Agauin ,thanks for the help.

Fred

It's kind of funny how such a little Problem like a missing Gasket could cause so much trouble.

We don't know it is that, yet.

Good Point. I guess I'll have to wait and see if the new Gasket solves my Problem.

I'd be looking very carefully at the inlet manifold - between the throttle body and the head. I'd have thought that's be where unmetered air would get in, either with a cracked manifold (pretty common) or a bad seal or some hose or other open to atmosphere.

would probably also cause idle problems

(have had idle issues when my intake cracked on my gts)

When I had running at an idle, I sprayed the intake Manifold with Brake Clean and nothing happened, but as soon as I sprayed the Airbox, it died right away. I will check again after I replace the the Airbox Gasket and I'll check the Vacuum hoses as well.

Fred

Hallo again. Lastime I wrote I was waiting on the Airbox Gasket.
Recieved it on Friday put it on on Sunday and now it won't start at all. It turns over and wants to start, but keeps Flooding. I took the Sparkplugs out and looked at them and found that they were soaking wet. I cleaned them up, put them back in and to start her again, but no such luck.Looks like I'll have to take her apart after all. I hope that it's just a Seal. Anything else is going to be pretty expencive.

Fred

Sounds like the injector is on permanently. Remove it and let it point into some container, then switch on. Hopefully it'll not squirt at all. Then try to start - it should squirt in pulses, and if I remember correctly stop squirting after a few seconds.

Again, IIRC, if it doesn't start in the first few seconds, it shouldn't start if you carry on turning it over.

Okay. I'll try it out. Thanks for the Tip

Fred

Well I'm backe again to give an Update. First off I did exactly what jimc proposed and checked the Injecter and found the it had a defect. It refused to close and kept pumping too much Fuel in the cylinder and was causing it to Floodout. I ordered a new Injecter and on Satursday replaced it and she started right away. The day after I replaced the Injecter I took her out for Testdrive and I am happy to say that my Problem has been solved. For all of you who offered your Advice, I am eternaly greatful.
And to jimc for hitting the proverbial Nail on the Head, I give a big Thumbs up.

Thank you very much Gents .

Hillbilly Fred

Hello Gents. I'm back again hoping for some more help. This Morning I got on my Roller to go to Work. Started her up. The Idle was really good, but when I started off, I had just reached the door of our underground Garage (ca. 10 Meters) and then suddenly she died on me and wouldn't start anymore. When I tried to Start her up again, she just wouldn't 'start anymore and it smelled like she was dumping Fuel again. I am completely at a loss right now. Can someone please help? I've replaced the Fuel Injector and the Inlet Manifold + Gasket and it actually ran very good for a while, but she started acting up again and today was the Tip of the Iceberg. I really need some advice.

Thanks Fred

What is this "Roller" you are referring to? Perhaps pet name for your MP3?

This latest issue sounds electrical in nature.

Start with the basics: load test battery, replace battery if over 3 years old, check all connections, clean all earth/ground connections, relays, fuses, etc, etc, etc

Do you have a spark?

Hallo sbaert
Did I say Roller? My Bad! Although as an afterthought, that is what they call them here in Germany. I get your point about checking the connections though, but the Battery is only a year old. I did charge it up yesterday and I plan on doing a Testdrive around the Block. Let me make a point though. As I was starting it Yesterday to go to Work, I notice that a Service Wrench did show up on the Display for a few seconds before it started running and after that, it repeatedly showed up when I tried several times to restart it. I'm Hoping that it (just according to said symbol) actually needs a service and not that it means that I have a much bigger Problem than I think I do . Thanks for the tip with the connections. I will look into that and keep you posted.

Many Thanks Fred

Hallo ArnoEn.
I do have a Spark and thanks for asking.

Fred

Have you tried to pull out the fuel injector and check the spray patern?
To check if there is fuel.

I recently had an intermittently failing ingnition load relay. This relais powers the fuelpump, injector and ingition coil.

The engine stumbled during the ride, some times would not start at all. And moments later everything was ok again.

Maybe you have the same issue?

Engine Stalled during ride

I don't think that's the Problem I have, because mine doesn't stumble or quit running after 30 seconds or so. Mine dumps Fuel by first start of the Day, but if and when it finally gets up to Running Temp.,it runs like a Charm and doesn't smell like it's Farting gas Fumes out through the Exhaust Pipe. It has never done this before until recently.
Thanks for Input ArnoEn. If you or anybody else has any Idee what may be causing this, Feedback would be most Welcome.

Thanks again from the Hillbilly

P.S. The Injector is original Piaggio and it's brand-new.

I might be wrong, but I see two important things (especially if the injector is new and doesn't leak when tested):

1. There's excess fuel only during initial ignition when the engine is cold.
2. Once it reaches operating temperature, the problem stops and there's no excess fuel.

Seeing this, I'd be inclined to say the problem might be with the air and/or engine temperature readings the ECU receives from the sensors. Perhaps it thinks the engine is too cold and injects more fuel for initial ignition, not reducing it once it starts? If the sensor only reacts when the temperature rises significantly, meaning it's not working linearly, that would explain why it happens when the engine is cold but corrects itself once it warms up.

I would check the signals from the air temperature sensor and the engine temperature sensor (especially the latter). If possible, get a sensor and test it, or buy one; they aren't that expensive (around $50 for the coolant one). But first, check the wiring/connectors between the sensor and the ECU.

correct, it doesn't matter.

I recommend using an obd diag tool to check the water temperature, air temperature and air pressure.

and if you haven't already, clean the throttle body.

Thanks for the Tips Gents. I'll look into it and keep you Posted

Fred