T-Roc Diesel Black Smoke: DPF Regen Warning Signs

Had the same symptoms on a 2014 VW Golf TDI. The exhaust back pressure sensor was failing, causing incorrect readings to the engine control unit. This triggered the reduced power mode and prevented proper DPF regeneration cycles. The sensor malfunction meant the diesel engine could not accurately measure exhaust flow, leading to that black smoke and strong exhaust smell during acceleration. The low pressure warning is a clear indicator, the system thinks there is insufficient back pressure when there actually might be too much. The repair involved replacing the pressure sensor and performing a forced DPF regeneration to clear any buildup that occurred while the system was malfunctioning. Once fixed, the engine returned to normal power and the smoke disappeared completely. This is a serious issue that needs addressing soon, as continued driving can lead to permanent DPF damage and more expensive repairs. The faulty pressure sensor readings can also cause excessive fuel consumption and potential engine damage if left unchecked. Based on those symptoms, strongly recommend finding a workshop specialized in diesel engine diagnostics and DPF systems.

Thanks for detailing that repair fix. My VW actually ended up having the exact same issue. Your description matches what I experienced perfectly, the black smoke, reduced power mode and those DPF problems. Really helpful to know the exhaust back pressure sensor was the culprit in your case. Quick question, do you remember roughly what you paid for the sensor replacement and DPF regeneration work? Also curious if youve had any emission control or exhaust system issues since getting it fixed?

Since having the exhaust back pressure sensor replaced, the emission control system has worked flawlessly. The total repair came to 245€, which covered both the sensor replacement and a complete DPF regeneration cycle to reset the system. The diesel exhaust problems completely cleared up after the fix. No more black smoke, reduced power warnings, or DPF regeneration issues in the following months. The engine performance returned to normal immediately after the repair. Its really common for mechanics to misdiagnose this particular fault, but replacing that faulty sensor resolved all the exhaust system symptoms. Just make sure they clear all error codes and perform a proper regeneration cycle after installing the new sensor. Worth noting that proper maintenance and regular highway driving since the repair has kept the DPF system functioning as intended. No check engine lights or exhaust-related problems have returned.

Had my car fixed last week after getting your advice. The mechanic confirmed it was indeed the faulty exhaust back pressure sensor causing all those DPF issues. Ended up paying 280€ for the complete repair including parts and labor. The whole process took about 3 hours. They replaced the sensor, cleared the fault codes, and ran a forced DPF regeneration cycle. Really noticed the difference as soon as I drove it, no more black smoke, reduced power warnings disappeared, and the engine runs much smoother now. Been driving it daily for the past week without any problems. The strong exhaust smell is completely gone and acceleration is back to normal. The diesel engine performs like new again. Definitely worth getting it properly diagnosed and fixed rather than letting those DPF regeneration problems get worse. Really appreciate the detailed info you shared, helped me explain the symptoms better to the new mechanic I found. They knew exactly what to check and fixed it right the first time.