Fuel Injector Problems: Causes & Solutions

"Hello, I installed a new engine (Renault Kangoo 1.9D F8Q 630) because the old one had no compression. Since the brand new engine had an injection pump with an immobilizer, I installed the old pump. For the first two days, everything was fine, but from the third day onwards, the fuel injection system fault light came on. In the morning, during a cold start, it only starts after about 2-3 minutes, and sometimes it even stalls. Also, when I drive faster than 120 km/h, the glow plug warning light comes on, and the engine makes noises (like it's trying to glow)."
I also took it to Renault, and they found three errors: a fault in the coolant temperature sensor circuit, a fault in the load potentiometer circuit, and a fault in the early ignition solenoid valve circuit. They cleared all the errors, but the check engine light continued to illuminate, and Renault was at a loss.
Thank you for all the answers.


Best regards, D. Lehmann.