Description

This is a reconditioned Garrett GT20V (GT2052V) turbocharger for the Audi A6 2.5 TDI V6 engine, specifically engine codes AKE and AYM. As a variable nozzle turbine (VNT) unit, it provides excellent response across the rev range but requires correct engine operation to maintain its health.

At Gap Turbos, we have specialised in units like this since 1986. The Garrett GT-series VNT turbochargers fitted to these V6 TDI engines are generally robust, but they have several common failure points we frequently address. The most prevalent issue is seizure of the variable vane mechanism. This is almost always caused by an accumulation of carbon and soot deposits from the exhaust gas, which restricts or completely jams the movement of the vanes. This leads to incorrect boost pressure – either too low (underboost) or too high (overboost), often putting the vehicle into a ‘limp home’ mode. Another common fault lies with the electronic actuator that controls the vane position, which can fail electrically or mechanically. Standard wear and tear on the central housing rotating assembly (CHRA) is also expected over the life of the vehicle, leading to worn bearings and failed oil seals, identifiable by excessive noise or smoke.

Our service for this turbocharger is comprehensive. We can recondition your original unit, which involves a full strip-down, ultrasonic cleaning of all components including the VNT mechanism, and replacement of all service parts with new bearings and seals. The core is then balanced to specifications exceeding the original manufacturer’s. Alternatively, we can supply a fully reconditioned unit from our stock for a faster turnaround, or a brand new replacement. We also offer a full drive-in, drive-out fitting service at our Birmingham workshop, which includes cleaning the intercooler, intake pipes, and performing an essential engine oil and filter change to ensure the new turbo operates in a clean environment.

What this turbocharger fits

This turbocharger, OEM part number 059145702D (alternative part number 454135-5009s), is a direct replacement for the factory-fitted unit on the following vehicle:

• Make: Audi
• Model: A6 (C5)
• Engine: 2.5 TDI V6
• Engine Codes: AKE, AYM
• Power Output: 150 HP
• Years: 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005

All our reconditioned turbochargers are built in-house and come with a 12-month warranty. Please contact us with your vehicle registration to confirm fitment and receive an accurate quote.

Specifications

Vehicle fitment

• Audi A6 2.5 TDI V6

Common faults & troubleshooting

• Loss of power or ‘limp mode’: This is the classic symptom of a seized VNT mechanism, causing either overboost or underboost that the ECU detects as a fault.
• Excessive black smoke from exhaust: Indicates incorrect air/fuel ratio, often because the turbo is not supplying the correct amount of boost pressure.
• Loud whistling or siren-like noise: This sound, which changes with engine RPM, points to worn bearings or a damaged compressor wheel inside the turbo.
• Engine management light on: Diagnostic fault codes related to ‘Boost Pressure Control’ or ‘Charge Air Pressure’ often point directly to a faulty turbo actuator or stuck vanes.
• Blue smoke, especially on start-up or overrun: This is a sign that the turbocharger’s internal oil seals have failed, allowing engine oil to leak into the intake or exhaust system.
• High oil consumption: If the engine is using an unusual amount of oil with no obvious external leaks, it could be passing through failed seals in the turbocharger’s core.

Fitting notes for this unit

• Pre-fill with oil: Before connecting the oil feed line, you must prime the new turbo by pouring clean engine oil into the oil feed port and rotating the compressor wheel by hand until oil emerges from the drain port.
• Replace oil feed pipe: The original oil feed pipe is a mandatory replacement item. Carbon deposits can build up inside, restricting oil flow and causing immediate failure of the new unit.
• Use all new gaskets and seals: Do not reuse any old gaskets, copper washers, or seals for the oil feed, oil drain, or exhaust manifold connections to prevent leaks.
• Check for debris: Thoroughly inspect and clean the entire air intake path, from the air filter to the intake manifold, including the intercooler, to remove any debris from the previous turbo failure.
• Initial run-in procedure: After installation, start the engine and allow it to idle for at least 5-10 minutes. This ensures the turbo’s bearing system is fully lubricated before it is subjected to high rotational speeds.
• Torque settings: Adhere strictly to the manufacturer’s torque specifications for the manifold and exhaust housing bolts to avoid warping the flanges and causing exhaust gas leaks.

Alternative part numbers

This turbo is also referenced by:

• 454135-5009s — GT20V Turbocharger OE 454135-5009s (Audi A6 2.5 TDI V6, AKE/AYM, 150hp)

Frequently asked questions