I have a 2003 dodge ram 5.7 HEMI. It went into safe mode about a momth ago. I took it to a dealer where they replaced the pcm and it didn't fix it. After reading other forums I replaced the throttle body. Didn't work either. Then I replaced the bell crank sensor. That didn't work (used part). Figured maybe I got a faulty throttle body nope. Opened up the valve covers everything looks intact. Any other ideas? This truck is costing me a small fortune to fix. The engine and transmission ran strong until it went into safe mode. Red lightening bolt is flashing

Codes:
P0517
p2108
p2172
p2106

 

And why is this truck not back at the dealer ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????