I have a 1999 F250 7.3 with 122 thousand. The last few years, especially when cold the truck would surge violently but of course never did it when taken in and the diagnostics were "clear" (per Ford dealer, so who knows). A few weeks ago the truck began surging and stalling constantly with the SES light on. My Superchip typically, on "Towsafe" gave the code P 0603 on diagnostic. Checking the forum it sounded like a CAM sensor problem. I reset the program to stock which eliminated the service engine light and it ran rough but no surges/stalls. This at least got me to my mechanic where he changed the Cam sensor. The first time I started it at the shop right afterward it stalled at idle twice but the shop diagnostic didn't show anything. I returned the setting to Towsafe once home and it ran fine for a couple weeks. Then it started surging a little and stalled when at red lights. Again I ran the Superchip diagnostic and it now showed P 603 KAM error! It is nowhere near as bad as it was but occasionally when it sounds rough or stalls the SES light comes on (but is gone as soon as the truck is restarted). It may run fine for a couple days and then do it everytime on others. HELP! Could it be the ICP, anyway to check?
Sorry for the long post. John