F115 AETL 2005, missfires when warm

[Shuntti84]

Hello,

Im having issue with outboard, missfiring and stuttering when warm. Works perfectly when cold.
Motor is currently in Yamaha service partner, but they are struggling to find the issue.

Motor works perfectly for 20min - 40min driving, depending on ambient temperature. When it warms up, it starts stuttering and missfiring.
Diag does not report any errors.

Anyone has any good advices?

Br,
Sami

[TownsendsFJR1300]

Spark plugs.

[Shuntti84]

This problem was solved few hours ago by Yamaha dealership.

Problem ended up beeing fried ECU. Replaced and motor works like charm.

Propably bad connection inside ECU since it ran just fine when cold. I will rip ECU open to see failure point.