The ’03 model years seemed to have had the worst fuel injection control module (FICM) issues. Apparently a lot of ’03 model trucks came back to the dealer for FICM reflashing when a pilot injection feature, which was intended to reduce engine noise and improve emissions, would create timing problems on hot start-ups. The result of this was a rough-running, loping idle. Later-model 6.0L FICM calibrations didn’t have this pilot injection feature. Another issue, which can happen to any model year 6.0L, is that the internal circuit boards in the FICM burn up—and FICM’s aren’t cheap. Notice the designation written on the FICM in this photo (Bad).