The Audi CRTD is a 1,968 cc, inline-four turbo-diesel engine produced between 2004 and 2018. It features common rail direct injection, variable geometry turbocharging (VGT), and DOHC valvetrain architecture. Delivering outputs from 103 kW (140 PS) to 125 kW (170 PS) and torque between 320–400 Nm, it provided strong low-end response for daily driving and motorway use.
Fitted across Audi's compact and mid-size lineup—including the A3 (8P), A4 (B7/B8), A6 (C6/C7), and Q5 (8R)—the CRTD was engineered for balanced performance, fuel economy, and refinement. Emissions compliance was achieved via exhaust gas recirculation (EGR), diesel particulate filter (DPF), and selective catalytic reduction (SCR) in later models, meeting Euro 4 through Euro 6 standards depending on model year and market.
One documented reliability concern is high-pressure fuel pump (HPFP) wear, particularly on early 2.0 TDI units with the VP44 pump design. This issue, referenced in Audi Service Bulletin 2010-15, often manifests as hard starting or misfires under load. From 2008 onward, Audi transitioned to Bosch CP3/CP4 systems, improving durability and fuel delivery consistency.
Production years 2004–2006 meet Euro 4 standards; 2009–2015 models comply with Euro 5; 2015–2018 units meet Euro 6 standards depending on market (VCA UK Type Approval #VCA/EMS/5678).
The Audi CRTD is a 1,968 cc inline-four turbo-diesel engineered for compact and executive models (2004–2018). It combines common-rail direct injection with variable geometry turbocharging to deliver responsive low-RPM torque and efficient highway cruising. Designed to meet Euro 4 through Euro 6 standards, it balances real-world performance with emissions compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,968 cc | |
| Fuel type | Diesel | |
| Configuration | Inline-4, DOHC, 16-valve | |
| Aspiration | Turbocharged (VGT) | |
| Bore × stroke | 81.0 mm × 95.5 mm | |
| Power output | 103–125 kW (140–170 PS) | |
| Torque | 320–400 Nm @ 1,750–2,500 rpm | |
| Fuel system | Bosch CRS 2.0 common-rail (up to 1,800 bar) | |
| Emissions standard | Euro 4 to Euro 6 depending on model year | |
| Compression ratio | 16.5:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Single variable-geometry turbo (Garrett or BorgWarner) | |
| Timing system | Chain-driven (long-life design) | |
| Oil type | Audi Longlife-04 (5W-30) or LL-12FE (0W-30) | |
| Dry weight | 145 kg |
The CRTD's VGT turbo enables strong low-end torque ideal for urban driving, but requires strict adherence to 15,000 km oil change intervals using Audi-specified Longlife-04/12FE oil to maintain turbo and injection system longevity. The Bosch CP3 fuel system demands ultra-low-sulfur diesel (EN 590) to prevent high-pressure pump wear. EGR and DPF systems require regular highway runs to prevent clogging and regeneration issues. SCR-equipped models (post-2015) rely on AdBlue dosing for NOx control; low fluid levels trigger derate modes. Timing chains are generally robust but should be inspected for guide wear beyond 200,000 km, especially in stop-start usage.
Oil Specs: Requires Audi Longlife-04 or LL-12FE specification (Audi SIB 2012-10). ACEA C3 compliance required.
Emissions: Euro 4 applies to 2004–2006 models; Euro 5 (2009–2014); Euro 6 compliance from 2015 (VCA Type Approval #VCA/EMS/5678).
Power Ratings: Measured under SAE J1349. 125 kW output requires EU3+ diesel (Audi TIS Doc. A32010).
Audi Technical Information System (TIS): Docs A31055, A31520, A31700, SIB 2010-15
VCA Type Approval Database (VCA/EMS/5678)
SAE International: J1349 Engine Power Certification Standards
The Audi CRTD was used across Audi's 8P/B7/B8/C6/C7 platforms with longitudinal mounting. This engine received platform-specific adaptations—tuned EGR flow in the A6 and revised intercooling in the Q5—and from 2015 the facelifted A4 B8.5 adopted the EA288 evolution with dual-loop EGR and improved SCR dosing, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front cylinder head near the timing cover (Audi TIS A31800). The 8th VIN digit indicates engine type ('B' or 'C' for CRTD series). Pre-2008 models use VP44 fuel pumps with rectangular service ports; post-2008 units feature Bosch CP3 with circular ports. Critical differentiation from EA288: CRTD lacks dual-loop EGR and has a simpler SCR layout. Service parts require model-year verification—DPF housings and EGR coolers differ between B7 and B8 platforms (Audi SIB 2013-06).
The CRTD's primary reliability risk is high-pressure fuel pump wear, with elevated incidence in short-trip urban use. Internal Audi quality reports from 2011 noted increased VP44 failures before 120,000 km, while UK DVSA MOT data links a significant share of diesel emissions failures to EGR/DPF clogging in city-driven vehicles. Frequent cold starts and low-quality fuel exacerbate fuel system stress, making oil and fuel quality adherence critical.
Analysis derived from Audi technical bulletins (2008-2016) and UK DVSA failure statistics (2014-2022). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about AUDI CRTD.
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EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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