My idle surges really hard in the morning while warming up and now slightly after it warms up. At first it was only during warm up in the morning, but now its all the time. In the morning its 300-400rpm and once it warms up it'll surge 100-200rpm. I changed out the fuel filter and same problem. Seems to run ok while driving, but it *might* have a little less power. The PO I believe replaced the IP already, but the injectors and lift pump are definitely original. Truck has 165k on it...