Originally Posted by Jared Duramax
start with the filter then if that doesnt fix the problem you need to see what your rail pressure is you can do this either at the dealer if you know a tech they can put a pressure guage on in to see what your accutal rail pressure is. or if you know somebody with EFI Live you can have them do some logging. this will be the only way to start to figure out what the problem is with the surging. now i will say that my truck surges when its cold out and my reasoning is that the fuel is thicker and not allowing it to flow as easily but once its warm everything is fine. i think my problem is leading toward a prematurly worn CP3. you might also have this issue.
I changed the filter yesterday after hunting Easter Eggs; maybe just a little better. I hooked to the tractor and ran up the road about fifteen miles or so and it went limp three times. I really had to hoss it to get the code but it's still there (without the HP turned up). Before I changed the FPRV the engine would 'hunt' when idling; it's smooth now so I'm confident that the valve must have been at least part of the problem.
I noticed in your sig. that you have EFI live. Can you program around this kind of issue with that setup? CP3? What's that?