P0299 on Peugeot: How to Diagnose & Fix
Turbo/Supercharger Underboost Condition
3 Peugeot models · 3 documented issues · 3 critical · $400-$2,600 repair
P0299 on Peugeot by model: symptoms, diagnosis and fix
The turbocharger oil feed and return lines develop leaks on the 1.6 THP engine, leading to oil consumption and blue exhaust smoke. The turbo bearing seals also deteriorate with extended oil change intervals.
Common Symptoms
- Blue exhaust smoke
- Oil consumption increase
- Turbo whine changes pitch
- Oil pooling near turbo
How to Fix
Replace the turbo oil feed and return lines with updated gaskets. If bearings are worn, a turbo rebuild or replacement is necessary. Use manufacturer-recommended oil change intervals.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- EP6DT turbocharger oil-feed pipe with banjo hardware, OE 037956
Confirm VIN, turbo configuration and original pipe before purchase.
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Sources for this issue (1)
The THP turbocharger develops oil leaks from the feed and return lines, and the turbo bearing seals degrade with heat cycling. Oil consumption increases progressively, and blue smoke appears under boost.
Common Symptoms
- Blue exhaust smoke under boost
- Oil consumption
- Turbo whistle changes
- Oil around turbo housing
How to Fix
Replace turbo oil feed/return lines and gaskets. Rebuild or replace the turbocharger if bearing play is detected. Ensure oil change intervals are not exceeded.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- GryphonTek EP6 K03/K04 turbo oil-feed and return-line kit, OE 037956 / 037979
Confirm VIN, engine/turbo tag and required restrictor; EP6CDTR RCZ R is not listed.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (1)
The 1.6 HDi diesel in the 308 I is notorious for turbocharger failure caused by oil starvation: carbon sludge — aggravated by extended oil intervals, wrong oil spec and leaking injector seals — blocks the tiny gauze filter in the turbo oil-feed banjo bolt and the feed/return pipes, starving the turbo bearing. Documented cases show oil pressure at the turbo far below the 2.3 bar minimum, and a replacement turbo fails again quickly if the sludged feed pipes, sump and pickup are not cleaned at the same time.
Common Symptoms
- Whining or whistling noise from the turbo
- Noticeable loss of power / limp mode
- Blue or grey exhaust smoke
- Rising engine oil consumption
- Engine management light with underboost fault
How to Fix
Replace the turbocharger together with new oil feed and return pipes and the banjo-bolt filter, drop and clean the sump and oil pickup, and flush the engine — about $1,200-2,600 all-in at an independent shop. Prevent recurrence with strictly shortened oil-change intervals using the correct low-SAPS oil and prompt attention to injector seal leaks.
Sources for this issue (7)
- Workshop repair: 1.6 TDCi Turbo Failure? Here's the real cause — autotechnicianarticle
- Tackling Turbo Trouble — PSA 1.6 HDI Engine — Professional Motor Mechanicarticle
- 1.6 HDi turbo problems — HonestJohn Good Garage Guidearticle
- How to prevent common turbo failures with the Peugeot/Citroen/Ford HDi engine — Hyperchipsarticle
- Trying To Avoid 1.6HDI Turbo Failure — French Car Forumforum
- 1.6 HDI Turbo problem (2009 308 1.6 HDi Sport) — Peugeot Forumsforum
- Turbo oil feed pipe filter — 2013 308sw 1.6eHDI — Peugeot Forumsforum
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 Peugeot?
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 Peugeot it is documented across 3 models: 207, RCZ, 308.
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 Peugeot?
Published repair estimates on Peugeot range from $400 to $2,600 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.