0445117021 — Technical Research
Bosch CRI3 piezo common-rail injector for the Audi/VW 3.0 V6 TDI (engine codes CLAB/CPNA/CMHA) fitted to the Audi A4/A5/A6/A7/A8 and Q7, plus the VW Touareg. Audi/VW OE 059130277CD / 059130277EJ; related Bosch 0445117022. Each injector carries a 7-character IMA/ISA correction code that is written per cylinder (adaptation channels 071-076) on fitment. Failures are driven by poor fuel filtration, contamination and back-leakage wear. Key symptoms: Rough idle / vibration; Hard starting; Loss of power / limp mode; Black smoke. Common failure modes: Piezo stack / internal wear; Water-in-fuel corrosion; Nozzle coking.
Bosch 0445117021 3.0 V6 TDI (CLAB/CPNA/CMHA) Common Rail Piezo Injector (Audi A6/A7/A8/Q7, VW Touareg)
Bosch CRI3 piezo common-rail injector for the Audi/VW 3.0 V6 TDI (engine codes CLAB/CPNA/CMHA) fitted to the Audi A4/A5/A6/A7/A8 and Q7, plus the VW Touareg. Audi/VW OE 059130277CD / 059130277EJ; related Bosch 0445117022. Each injector carries a 7-character IMA/ISA correction code that is written per cylinder (adaptation channels 071-076) on fitment. Failures are driven by poor fuel filtration, contamination and back-leakage wear. Key symptoms: Rough idle / vibration; Hard starting; Loss of power / limp mode; Black smoke. Common failure modes: Piezo stack / internal wear; Water-in-fuel corrosion; Nozzle coking.
A leaking injector unbalances cylinder fuelling on the 3.0 V6 TDI.
Excess back-leakage drops cranking rail pressure.
Out-of-range delivery or rail-pressure deviation cuts power.
Poor atomisation over-fuels the cylinder.
Cylinder-specific injector or fuel-metering codes.
- InstallationWrite the 7-character IMA/ISA correction code per cylinder (adaptation channels 071-076) with VAG ODIS/VCDS before road test.
- InstallationRenew the combustion seal and clamp hardware; torque to spec.
- MisdiagnosisRead live back-leakage data to find the weak cylinder before removal.
- WarningFix contamination (filter/water/debris) first; the 3.0 V6 TDI is sensitive to fuel quality.
- TestingBench-test on a piezo-capable CR tester across delivery and back-leakage points before refit.
What is Bosch injector 0445117021?+
A Bosch CRI3 piezo common-rail diesel injector for the Audi/VW 3.0 V6 TDI engine. Audi/VW OE 059130277CD / 059130277EJ.
Which vehicles use 0445117021?+
Audi A4/A5/A6/A7/A8 and Q7, plus the VW Touareg, with the 3.0 V6 TDI (CLAB/CPNA/CMHA) engine.
Is it solenoid or piezo?+
It is a Bosch piezo (CRI3) common-rail injector.
Does 0445117021 need coding?+
Yes - write the 7-character IMA/ISA correction code per cylinder (adaptation channels 071-076) with VAG ODIS/VCDS.
What are the OE part numbers?+
Audi/VW 059130277CD and 059130277EJ reference Bosch 0445117021; the related number is 0445117022.
How is 0445117021 different from 0445117022?+
0445117022 is a related Bosch number in the same 3.0 V6 TDI family; always match the OE number and IMA code requirement for the exact variant.
What are the symptoms of failure?+
Rough idle, vibration, hard starting, black smoke, power loss/limp mode and an EML.
Why does my 3.0 TDI run rough?+
A worn or leaking injector unbalances fuelling; read live back-leakage data and bench-test the weak cylinder.
What causes these injectors to fail?+
Poor fuel filtration, contamination and back-leakage wear - fix the cause first.
Does a remanufactured 0445117021 perform like new?+
A properly remanufactured injector is bench-tested and recalibrated to the Bosch plan, then IMA-coded on fitment.