With this Land Rover Discovery, we found ourselves confronting a series of complex issues. The saga began with the customer booking in as their EML had come on. The vehicle wasn’t going into limp mode but was losing power and going through a lot of oil.
Our diagnosis revealed a failed diesel particulate filter (DPF), a critical component tasked with reducing harmful emissions. As the DPF faltered, its internal structure crumbled, releasing fragments that wreaked havoc within the engine’s intricate ecosystem.
These fragmented particles took an unexpected turn as they found their way into the low-pressure Exhaust Gas Recirculation (EGR) system. Designed to recirculate exhaust gas treated by the DPF, the EGR system encountered an unwelcome obstruction, leading to a cascade of consequences.
Within the passages of the EGR system, the debris encountered the EGR cooler filter gauze, a crucial barrier intended to prevent contaminants from infiltrating vital components. The filter gauze succumbed to the onslaught, allowing minute particles to bypass its defences and infiltrate the turbocharger.
The turbocharger, a powerhouse of the engine, bore the brunt of this intrusion. The impeller blades, essential for compressing incoming air, fell victim to the abrasive debris, suffering damage that compromised their integrity.
Take a look at the picture below. On the right, you can see the damage impeller blade.
As the turbocharger struggled to perform its duties, a chain reaction of complications ensued. Oil seals within the turbo faltered under the strain, resulting in oil flooding the intake system. With the engine starved of proper lubrication, the timing chain, a vital component orchestrating the engine’s synchronicity, succumbed to the strain, with the chain elongating beyond its intended limits.
Amid these challenges, our inspection uncovered yet another concern: malfunctioning glow plugs. These are responsible for pre-heating the combustion chamber, playing a pivotal role in facilitating the engine control module’s ability to conduct a DPF regeneration. Their failure further exacerbated the vehicle’s predicament, hindering its ability to undergo essential maintenance procedures.
With a thorough understanding of the work required, our team embarked on a comprehensive repair mission. The damaged turbo and timing chain was replaced with precision, restoring the engine to its former glory. A new set of glow plugs found their home within the engine, ensuring optimal performance and resilience against future challenges.
The Land Rover was finally running as it should again. But let this be a lesson to you in the importance of regular maintenance. The warning signs were there, and had we seen this vehicle when it first experienced problems, we may have been able to reduce that repair bill.