A Transporter with rough running and P0191 needs more than a code-to-part lookup. This vehicle-specific guide builds on our general fuel-pressure guide and highlights a documented T6 diagnostic example.
Source example: T6 2.0 TDI, 2016-2019
HELLA’s T6 repair note describes uneven running with engine or glow-plug warning indications and a possible P0191 entry. It calls for checking relevant electrical and mechanical systems, including the supply, before considering the fuel-rail pressure sensor. The example does not establish an ECU failure or make the sensor the answer for every van.
Organise the fault history
- Give the engine code and vehicle year alongside the full P0191 description.
- Describe whether the engine starts normally and when the rough running occurs.
- Include the full scan, recorded conditions and any existing pressure-data report from the garage.
- List previous fuel-system, sensor or wiring work and whether the symptom changed afterwards.
- Tell us whether the fault is persistent or has only been recorded once.
What a useful result should explain
Ask the diagnosing workshop to explain which observations support its conclusion. A repair record is more informative when it states the original complaint, the evidence used to select the repair and how the complaint was checked afterwards. Keep that record with the vehicle so future investigations do not start from a list of replaced parts alone.
Fuel-system work should follow the correct professional procedure. Do not loosen high-pressure fuel lines or probe unidentified connections to investigate a code yourself.
Next step for ECU or wiring support
Read the broader P0087, P0088 and P0191 guide and prepare a repair enquiry. AXION welcomes owners and garages across the UK; contact the team before posting a module. Vehicle-side diagnosis may be needed to establish the next step.