Modern Vespa

I have changed ecu , fuel pump , injector, spark plug and cap , ht lead , the brown key has been matched to ecu .
Turns over but will not start even though the immobiliser light flashes correctly. Battery is ok
Any ideas please at a loss of what it is
Thanks

Was it a new or secondhand ECU?

Not sure how it works on a Vespa but I'm currently having an ECU replaced on my car. A new ECU has to be programmed in, or if I buy a secondhand ECU, I also have to have the clocks and a few other items that are all coded in the same loop - or it won't work.

Does the mileage display correctly?

Hi Yes it does and all appears correct

And it's a second hand ecu

My guess is that the ECU is coded to the old Vespa and doesn't match.

For my car, I've had to buy a secondhand ignition barrel, an airbag controller, new speedo / clocks and the ECU as a set from the same vehicle. Fitting a secondhand ECU on its own, wouldn't allow the car to start.

If it turns over when you press the start button as you say then it's not a problem with the immobiliser/key.

Why did you replace all these parts?

PS i happily used a 2nd hand ecu for a long time in my Vespa

If a secondhand ECU does work standalone, then are you sure this ECU isn't also broken?

And are you sure the ECU is from the same model?

What was the problem that led you to replace all these parts?

It cut out as if it had run out of fuel, them would not start again

Also when new fuel pump fitted it started up ran on idle soon as open throttle it cut out

Ht coil?

And do you hear the fuel pump?

Maybe a relay?

Yes fuel pump working and ecu is, tried it out on another scooter