Specialist ECU Send-In

ME3.8 Tuning

Bosch ME3.8 calibration for AGU, AEB, AJL and APX 1.8T applications.

Stage 1

For standard vehicles or exhaust and air filter upgrades only.

£250

Order Stage 1

Stage 2

For FMIC and K03/K03S turbo setups. Hybrids excluded.

£300

Order Stage 2

Hybrid / Injectors

Custom calibration for hybrid turbo, injector or higher-spec hardware.

£450

Order Hybrid / Injectors

Immobiliser Off

ME3.8 immobiliser off service by ECU send-in.

£120

Order Immobiliser Off

Important OTP Chip Information

ME3.8 ECUs use OTP memory. Chip-level programming, chip replacement or conversion may be required before reliable tuning. Typical turnaround is 2–5 working days from ECU arrival.

Order ME3.8 Tuning

Bosch ME3.8 Explained

What Is ME3.8 Tuning?

ME3.8 is an older Bosch engine control unit commonly fitted to early VAG 1.8 Turbo vehicles. Unlike many newer ECUs, these units often require bench/chip-level work rather than a simple OBD remap.

Why It Is Different

Many ME3.8 ECUs use OTP memory, meaning the original chip cannot simply be overwritten like newer ECUs. The ECU may need to be opened, the original memory removed or bypassed, and a programmable chip fitted before tuning can be completed reliably.

What Can Be Tuned

Fuel, ignition, boost control, torque delivery, throttle response, injector scaling and supporting hardware calibration can be adjusted depending on the engine setup, turbo, injectors, MAF and intercooler arrangement.

ECU Send-In Service

ME3.8 work is ECU send-in only. Remove the ECU, send it to CRF Tuning, and we complete the chip work/calibration before returning it ready to refit. Contact us before ordering if you are unsure which ECU you have.

Supported Vehicles

Common ME3.8 Applications

Support depends on ECU number, engine code and hardware setup. The vehicles below are common examples.

VW Golf GTI Mk4 1.8TAGU engine code

Audi A3 8L 1.8TAGU engine code

Audi A4 B5 1.8TAEB / AJL engine codes

Audi TT 8N 1.8TAPX engine code

Seat / Skoda 1.8T modelsSelected ME3.8 ECUs by ECU number

Other VAG 1.8T ME3.8Checked case-by-case before work starts

ME3.8 Options

Available Work

Stage 1 - £250

For standard cars or cars with basic exhaust/intake improvements. Improves power, torque and drivability while keeping the setup suitable for daily use.

Stage 2 - £300

For cars with supporting hardware such as FMIC and K03/K03S turbo setup. Hybrid turbos are not included in Stage 2 pricing.

Hybrid / Injectors - £450

For hybrid turbo, injector upgrades, changed MAF scaling or higher-spec hardware requiring custom calibration work.

Immobiliser Off - £120

Useful for replacement ECUs, engine conversions and non-start immobiliser-related issues where immo off is required.

Recommended Add-Ons

Customers often add immobiliser off, injector scaling, fault-code/DTC work, or hybrid calibration depending on their setup.

Order Immobiliser Off

Before Ordering

Please contact CRF Tuning with your ECU part number, engine code and full hardware list. This confirms whether your ECU is supported before sending it in.

Contact Before Ordering