If your Land Rover Defender Td5 or Discovery 2 Td5 has begun to misfire, cut out, or feel sluggish and uneven, there’s a strong chance the injector harness is to blame. This small, affordable component—often called the “injector loom”—can cause major running issues when it starts to fail, but fortunately, it’s an easy fix.
 
What is the injector harness?
The injector harness sits beneath the rocker cover and links all five injectors to the engine’s main wiring loom. One end plugs directly into each injector, while the other passes through the rocker cover and connects to the main loom via a round or oval plug. The correct part for all Td5 engines fitted to Defender (1999–2006) and Discovery 2 (1998–2004) is AMR6103.