2003 VMAX HPDI 150 - Is this right?

[bang2568]

I have this motor that is new to me. I had the dealer rig in onto my existing boat. When I have the boat in idleing it is runs smooth and quite. When I disengage the shift lever and run the warm up lever up, the rpm's rise slowely in like a "maaaaauuuwwww" sound. It does not have snappy throttle response. It is like it is under load or down a cylinder. It runs strong up to speed. a solid 45 - 50 with an 18 foot aluminum deep v fish and ski.

As is said this motor is new to me and I am wondering if I should be expcting the snappy trottle response or is there an override to prevent overrevving when the neutral lock button is disengaged.

Thanks for the help.

[PRO XS Skeeter]

I know my 200 hpdi would drop 2 cylinders if it was not in gear. Made the same sound as yours.

[Vyper202]

HPDI has a neutral safety switch, they wont rev/idle up in neutral over about 1000 RPMS.