150 HPDI idle problem. - The Hull Truth

Chris996 · 05-13-2008, 05:06 AM

Ive a wandering idle on my starboard 150 HPDI. On the muffs , she will raise and lower from 800 to 1200 and wont settle down even when warm. Plugs look fine. No alarms.
One odd note is when put in gear the idle seems to settle at 800.
Sorry to be so vague , as I had the engines off the boat this year and just re rigged them. Just hoping for some ideas where to start looking for something that would give these symptoms. Port engine seems fine.
Thanks

A1 Outboard · 05-13-2008, 05:10 PM

It's possible that the throttle cable is not adjusted correctly since the motors were on and off the boat. The HPDI is versy sensitive to linkage adjustment and throttle position sensor idle voltage adjustment. All 6 throttle plates have to have all the play removed and make sure they close full all at once, plus start to open all at once. There is a service bulletin that describes how to set the throttle position sensor, TPS, voltage as the idle speed.

Of course everything else has to be adjusted correctly and within specs and the plugs in good conditon. Make sure that fuel pressure is steady and around 35 psi at all speeds.