6.0 with code P0488 won't clear
I'm working on a friends 2004 6.0 f-350 with 95k miles that had codes p01334 and code p0488. I pulled the egr to check it and it appears to be clean. Took the truck to a ford dealer and they told me is needed a throttle plate. So I spent the $800 and put one on. Cleared the codes and drove the truck. No check engine light. Shut the truck off and the next morning when I fired it up had a check engine light again with code p0488 again. So I cleared the code turned off the ignition and turned the headlamps on. Disconnected batteries and let sit for 10 min. Reconnected and performed the relearn process and then performed a 15 mile drive cycle and never had the code come back on. Turned the truck off and fired it right back up and had code p0488 come right back! Any ideas? BTW when I picked the truck up from the dealer I asked them if the engine control unit will need to be reflashed (since I read the tsb about these exact codes and that was the repair) and they said no. Just install the throttle plate and clear the codes and it would be good to go. And advice would be greatly appreciated since I'm about to pull all my hair out lol.