Hello, all. I live in CA and have a 99 F250 with the 3 codes. I have a GPR with bus bar and NOT a GPCM. I changed the GPR, all new glow plugs, and even the wiring harness on the right bank (soldered it on). I still get both P1391 and P1393 codes. I checked the bus bar and connections look fine and tight. Truck runs great and starts right up. Any suggestions on what else I can try? My emissions test is coming up soon and it looks like I may be failing unless I can fix it!

Also, just recently my WTS light doesn't come on anymore and it's also throwing code P0381. This started a few weeks ago.