Exhaust knocking from underneath, DPF warning light on constantly, and the mechanic in the next workshop suggested "cutting the filter out"? SMotors in Kraków regenerates DPF filters using the hydrodynamic method — legally, in compliance with the vehicle type-approval and at a fraction of the cost of a new filter. Cutting out a DPF has been illegal since 2009 and is detectable at every MOT from 2026 (stations now have particulate counters). We weld silencers and exhaust pipes using TIG (stainless steel inox) for lasting results. We regenerate and replace catalytic converters, replace lambda sensors with ECU adaptation reset. We diagnose AdBlue/SCR systems before replacing expensive components. Written quote before every repair, flow measurement and fault code clearing included after.
Book exhaust serviceHydrodynamic DPF regeneration removes soot and ash in 2–6 hours, restoring flow to approximately 99% of new. Before and after we measure with a pressure gauge — the customer receives a document with results. After regeneration we clear fault codes (P2463, P2002) and reset the regeneration counter. We do not cut out DPFs — it is illegal and detectable at every MOT from 2026.
We weld using TIG (stainless steel / inox) and MIG/MAG (mild steel). Stainless pipes are many times more corrosion-resistant than mild steel — "the exhaust rusts every two years" is a mild-steel problem, not inox. We repair exhaust flex pipes, resonators and cracked silencer bodies. Silencer replacement when welding is no longer sufficient.
Catalytic converter regeneration (500–2000 PLN) is many times cheaper than a new unit (2000–5000+ PLN). A rattling catalytic converter means a crumbling ceramic substrate — risk of engine damage from ceramic fragments. We diagnose with an endoscope before deciding on regeneration or replacement.
The lambda sensor controls the air-fuel mixture — a worn one causes increased fuel consumption, rough running and accelerated DPF clogging. After replacement we always reset ECU adaptations (a step many workshops skip). We also diagnose the AdBlue system: injector, pump, NOx sensor and heater.
We connect a scanner and read exhaust system fault codes (DPF, EGR, lambda, AdBlue). We inspect the car on the lift — we assess silencer, flex pipe and catalytic converter condition.
We measure DPF flow with a pressure sensor and endoscope camera. We assess whether regeneration is possible — if not, we tell you before any decision is made.
A quote with repair scope (regeneration / welding / replacement) and price is provided before work begins. No surprises on the invoice.
DPF regeneration (2–6 h), silencer welding or lambda sensor replacement. After repair we reset the regeneration counter and clear fault codes via scanner.
We measure DPF flow after regeneration, check for leaks and issue a document with measurement results. Workmanship warranty included.
Hydrodynamic DPF regeneration costs 500–700 PLN for passenger cars. That is 75–90% less than a new filter (2000–4000 PLN + fitting). After regeneration we measure flow and clear DPF fault codes via VCDS or a multi-brand scanner.
Yes — regeneration restores the filter to approximately 99% of factory performance and is fully legal under Polish law and the vehicle type-approval. Cutting out the DPF is illegal (fines of 500–5000 PLN, loss of type-approval, insurance refusal). From 2026 MOT stations use particulate counters that detect a missing filter — do not take the risk.
Exhaust welding costs 60–225 PLN depending on scope and material. We weld stainless steel (TIG) and mild steel (MIG/MAG). Middle silencer replacement: 170–300 PLN, rear silencer: from 130 PLN. Prices include labour.
If blockage exceeds approximately 80% or the car is in limp mode, self-regeneration by driving on a motorway is ineffective — limp mode restricts power and prevents full filter burn-off. If the DPF light is on permanently or power is reduced, visit a workshop.
Lambda sensor replacement costs 350–1000 PLN in total (part + labour). After replacement we always calibrate ECU adaptations — without this the engine may still run rough despite the new sensor. We use OEM sensors (Bosch, Denso, NGK).
The AdBlue/SCR system requires specialist diagnosis before expensive parts are replaced. AdBlue pump repair: ~4000 PLN, new pump: 4000–12,000 PLN. NOx sensor repair: ~2500 PLN. Low-quality AdBlue fluid destroys the injector. We diagnose first and repair only what needs replacing.