P0402 on Land Rover
Exhaust Gas Recirculation Flow Excessive
P0402 on Land Rover vehicles indicates exhaust gas recirculation flow excessive. Au7o has documented this code across 1 Land Rover model — most commonly on Discovery. P0402 means the Exhaust Gas Recirculation (EGR) system is flowing too much exhaust back into the intake. The EGR system intentionally routes a small amount of inert exhaust gas into the engine to lower combustion temperatures and reduce nitrogen-oxide emissions, but the flow must be metered precisely. When the PCM determines the flow is excessive — often because the EGR valve is stuck open or letting gas through when it shouldn't — it sets this code. Too much EGR can cause rough idle, stalling, hesitation, and a check engine light. Typical repair costs on Land Rover range from $2,000 to $5,000, depending on the specific model and root cause.
Common Causes of P0402
- •EGR valve stuck open or not closing fully
- •Failed or sticking EGR valve diaphragm/solenoid
- •Carbon buildup holding the EGR valve open
- •Faulty EGR position or differential pressure (DPFE) sensor
- •Leaking EGR valve gasket or pintle seat
- •Vacuum control or solenoid fault commanding EGR open
- •Wiring or connector problems in the EGR control circuit
P0402 on Land Rover by Model
Land Rover Discovery(1 issue)
- EGR Cooler Failure and Coolant Leak (TDV6/SDV6)2010-2018
The EGR cooler on the 3.0L TDV6 and SDV6 diesel engines develops internal cracks that allow coolant to leak into the exhaust system. This causes white smoke from the exhaust, gradual coolant loss, and can contaminate the DPF. In the worst case, coolant enters the combustion chambers and causes hydrolock. This is considered one of the most serious diesel Discovery failures.
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View P0402 across all makes →Frequently Asked Questions
What does P0402 mean on Land Rover?▼
P0402 stands for "Exhaust Gas Recirculation Flow Excessive." P0402 means the Exhaust Gas Recirculation (EGR) system is flowing too much exhaust back into the intake. The EGR system intentionally routes a small amount of inert exhaust gas into the engine to lower combustion temperatures and reduce nitrogen-oxide emissions, but the flow must be metered precisely. When the PCM determines the flow is excessive — often because the EGR valve is stuck open or letting gas through when it shouldn't — it sets this code. Too much EGR can cause rough idle, stalling, hesitation, and a check engine light. On Land Rover specifically, this code is documented across 1 model.
What causes P0402 on Land Rover vehicles?▼
Common causes on Land Rover: EGR valve stuck open or not closing fully, Failed or sticking EGR valve diaphragm/solenoid, Carbon buildup holding the EGR valve open, Faulty EGR position or differential pressure (DPFE) sensor, Leaking EGR valve gasket or pintle seat. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0402 on a Land Rover?▼
Repair costs on Land Rover range from $2,000 to $5,000, depending on the specific model and root cause.
Which Land Rover models have P0402 documented?▼
Au7o has documented P0402 on 1 Land Rover model: Discovery.