P0299 on Land Rover: How to Diagnose & Fix
Turbo/Supercharger Underboost Condition
1 Land Rover model · 1 documented issue · $300-$1,600 repair
P0299 on Land Rover by model: symptoms, diagnosis and fix
The Euro 5 2.2 added a DPF, and the EGR/DPF/variable-vane turbo behave as one interlinked system that clogs with soot on short-trip, low-speed use. A carboned EGR dumps extra soot into the DPF, the DPF blocks and forces failed regens (diesel washes into the sump and the oil level rises), and carbon from the EGR/blow-by builds on the VNT turbo vanes so they stick and the engine drops into underboost/limp mode. The EGR cooler can also crack internally and let coolant into the exhaust circuit. This is the cluster of faults that puts a 2.2 into limp mode again and again.
Common Symptoms
- Repeated limp mode / power loss when hot or under load
- DPF warning light
- Black smoke under acceleration
- Rising engine oil level and diesel smell
- White smoke / coolant loss / mayo on filler (EGR cooler)
- Rough loping idle
How to Fix
Restorer bulletproofing for an off-road/show build: (1) Where legal for use, fit a proper EGR blanking/delete plate with a matching ECU remap so the intake stops sooting up at source (a widely-offered Puma upgrade) — for road-legal cars, decarbonise the EGR every ~40k and replace a cracked EGR cooler with an uprated unit. (2) Walnut-blast or chemically de-coke the VNT turbo vanes and free/replace the corroded vacuum actuator rather than condemning the turbo on a P0299 alone. (3) Strip and clean or recore the DPF and run an Italian-tune-up / forced regen; only replace if soot loading is past recovery. (4) Lock in 8,000-mile low-SAPS (WSS-M2C913-C) oil changes and a known-good thermostat so regens complete and diesel dilution stops.
Sources for this issue (3)
P0299 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0299 mean on a Land Rover?
P0299 stands for "Turbo/Supercharger Underboost Condition." P0299 means the engine computer detected an underboost condition — the turbocharger or supercharger is producing less boost pressure than the PCM expects for the given conditions. The computer compares the manifold/boost pressure sensor reading to a target based on engine load, and when actual boost falls short, it sets this code. The most common real-world cause is a leak somewhere in the intake/charge-air path. You'll typically feel reduced power or sluggish acceleration, and the engine may go into a reduced-power mode. On Land Rover it is documented across 1 model: Defender.
What are the most common causes of P0299?
The most common causes of P0299 are: Boost/intake leak (cracked or loose charge-air hose or intercooler), Faulty or sticking turbo wastegate or actuator, Stuck or clogged variable-geometry turbo vanes (VGT), Faulty boost pressure or MAP sensor, Leaking or disconnected vacuum/boost control lines, Restricted air intake or clogged air filter, Failed boost control solenoid, Worn or failing turbocharger. The specific cause varies by vehicle.
How much does it cost to fix P0299 on a Land Rover?
Published repair estimates on Land Rover range from $300 to $1,600 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0299 on a different make?
View P0299 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.