hey guys ive got a 2015 gmc sierra 1500 stock had rough idle had new injectors, plugs wires and coils put in. when i started up it was rougher than before with reduced power
have a couple codes
P0208 Cylinder 8 injector circuit/open
P0300 Random misfire
P050D Cold start rough idle
P1249
Any Insight would be greatly appreiciated truck has 160k

 

Looks like the cylinder 8 injector is causing the other codes. I would start by carefully investigating the number 8 injector harness and wiring.

 

I got new injectors and swapped wiring it did have a cut runs a little better but still flashes service engine