Land Rover found the No.4 diesel fault code p0 19 1.

There is only the fault code of p049 1. P049 1 fault code, applicable to all automobile manufacturers, indicates insufficient secondary air injection system flow (line 65438 +0) (secondary air injection system insurance flow (line 65438 +0)).

When the engine is just started, the secondary air injection system (air) oxidizes harmful gases such as hydrocarbons and carbon monoxide by forcibly inputting air into the exhaust manifold. This process also accelerates the preheating process of catalytic converter. If the electronic control unit (ECU) finds that there is not enough air flow change when the secondary air injection system pump is alternately turned on and off, this fault code will appear.

The failure causes include air pump output blockage, air bypass solenoid valve leakage or blockage, air bypass solenoid valve stuck, valve failure, electronic air jet pump pipeline leakage, electronic air jet pump failure, electronic control module (PCM or ECM) failure, etc.