I have a Regulator in the Bahamas fitted with twin 2004 Yamaha 300 HPDI which has been running fine until now, 540 hours both engines.
a problem has just developed with 1 engine.
will not idle out of gear and stalls, belches smoke when first started, 20% down on engine revs and power for same throttle as other engine, and consuming 30% more gas than other engine at identical RPM.
plugs changed with no effect.
yamaha dealer and technician cannot identify any fault, even with Yamaha diagnostic tools!!
anyone had a similar problem, and what was the cause??