Cummins ISX 600 fault code

Well, if your engine is running poorly when warn outside, but good when cold I would guess maybe fuel lines or something before the engine.

 

I had the same problem before Volvo770/2001/500ISX , after spending $ 3000 at several Cummins locations for a new Davco water separator , new fuel lines (all of them) and new pickup fuel pump (they told me that the pump put air in the system) i found that in fact the problem was the " FUEL SHOT-OFF SOLENOID" ,... the solenoid that cut the fuel when you turn the key off , is located in the top off the fuel filter. Be careful , buy all the parts and components of the solenoid including the magnet , is important !!! , cost me some 135$ if i remember good . What happens is that after it cuts the fuel it will remain stuck in a bad position and will restrict 40% of incoming fuel . The check engine will go on when decelerating or going downhill , when cold outside it will almost never happen.

 

Good to know!

 

what number code comes up?

 

do you experience engine run on? if so, more than likely an injector. if not, we may have a high pressure relief valve getting stuck open. obviously, everything on the pressure side is okay if you're not getting this code accelerating under load. if you had return line restriction, it wouldn't set this code and it would run rough. the only solution left is return fuel is not being kept in the ifsm or cylinder head while decelerating.

 

cylinder imbalance and fuel pressure, although with the FMI for the PID 094, its hard to tell what exactly is happening. although, i'm sure its a FMI 1, low fuel pressure. if those are the only two codes, then it may be just a coincidence of when this is happening. this may be sucking air, lift pump or gear pump going out. hard to say without knowing the fuel pressure readings.