Suzuki Marauder FI light flashing and not starting
 

Hi fellow bikers
I have a problem with my marauder not starting, the AA man came out and we did the spark plug test result low spark, he said it could be the coil. I got a coil although not the same year as close as I could get still not joy. I'm hoping to do a circuit test tomorrow, but thought I'd ask on a forum to see if anyone had had similar and got it resolved. I've booked it in on saturday with the dealer if i lose patience.
The Fi light flashing on off on off and it turns over starts, revs then dies. Worried it was the CDI unit but thats not cheap to just buy and see. I may also do an oil change and air filter check as some posts mention this as well as dirty fuel in the injection system.
So any comments will be gretfully received.

thanks for reading

Samantha