[Meathead]

im posting for my gf's father,
he has a 05 powerstroke harley davidson. the truck has a CAI, Turbo back exhaust and a tune.
since last week the truck seems to start and run rough. now if its cold and it start its fine, but if you drive to the store and back it has a hard time starting and once it starts it runs on less than8 cyl. but shut it off and KOEO a couple of times and its fine.
im a gm guy and i play with gas engines lol, but I have an understanding of diesels, i was thinking the glow plugs were going bad they have nearly 90k on them and they have had a rough life of towing.
also the fuel filters are past needing to change. that will be done today, but any ideas other than that? Im gona get it on a Modis next wk, but there are not any codes, im gona just be looking at reading then.
thanks in advance

 

[ZombieSoldier]

could be injectors gone bad, glow plugs, HPOP, a code, fuel filter, leaking o-rings, bad Camshaft Position Sensor etc

 

[Meathead]

Once I change his fuel filters, if the problem continues should i ohm the glow plugs?
And I had some one said removing the cab is easier than working on the truck through the engine bay? U guys heard of that? Seems like alot of work for glow plugs