VP 5.7GI goes into “Slow Mode”

[Sandcrazy]

So I have a 2010 5.7 GI Volvo Penta DPX that runs fine for the 1st few hours and then is going into slow mode (won’t run above idle) I can shut the motor off and it will run fine for about 30 seconds and then goes back into slow mode. I’m guessing there is a wire shorted somewhere, but puzzled as to finding it. I know there are ways to make a code reader to help at least track down the circuit to narrow down the search. My question is in all the research I have done, I have only found older versions and the OBD plugs are different than mine. Does anyone have an idea on where to look or how to proceed?

 

[alldodge]

can shut the motor off and it will run fine for about 30 seconds and then goes back into slow mode

I think you should start checking your fuel system first.
Dump fuel filter contents into a clear container to see if there is nothing but clear gas
Check fuel pressure at the rail

 

[Sandcrazy]

New fuel filter and when I shut the key off and fire it back up it runs perfect... only for about 30 seconds. Something is causing it to go into slow mode.

 

[alldodge]

Check your fuel pressure and if its good, your going to need a scan tool (Techmate or diacom software)

 

[GeorgeDes]

A slow mode condition is usually traceable to an overheat or oil pressure issue. Does not necessarily mean a major problem, it could just be one of the two sensors that feed the control unit or perhaps a wiring issue with them. The code reader will tell you which it is. What are your temp and oil pressure readings before going into slow mode?