2014 Chevrolet Silverado 3500HD No Boost - DTC P0281, P0284, P262B, U0198 After Turbo Replacement

Model: 2014 Chevrolet Silverado 3500HD Fault Code: P0281 Posted: 2018-10-17 09:59

I recently replaced the turbocharger on my 2014 Chevrolet Silverado 3500HD. After installation, I have confirmed no leaks and all connections are secure. However, I am experiencing no boost pressure. The vehicle is now displaying four diagnostic trouble codes: P0281 (Cylinder 7 fuel contribution and balance), P0284 (Cylinder 8 fuel contribution and balance), P262B (Control module power off timer performance fault), and U0198 (Lost communication with Telematics Control Module). I've verified the turbo installation and all associated wiring, but these codes persist. Any insights or troubleshooting steps for this combination of faults would be greatly appreciated.