GPF and OPF Particulate Filters

GPF OPF particulate filters are the petrol-side answer to the soot produced by direct injection. GPF (Gasoline Particulate Filter), OPF (Otto-Partikelfilter) and PPF are different names for the same component: a ceramic filter in the exhaust that traps particles from GDI/TSI/TFSI combustion, monitored by the ECU through differential pressure and temperature sensors.

How petrol regeneration differs from a diesel DPF

Petrol exhaust runs hot — often 600–700 °C in normal driving — so a GPF regenerates mostly passively whenever the engine spends time under load. What the ECU still has to create is oxygen: at stoichiometric mixture there is almost none left in the exhaust. Typical strategies are short fuel cut-offs on overrun and slightly lean phases that push oxygen through the filter, letting the stored soot burn without a dedicated “regeneration event” like on a diesel.

What the ECU watches

• Differential pressure across the filter — the main input for the soot load model
• Exhaust temperature before and inside the filter — to protect the substrate from overheating
• Mileage and driving-profile counters — plausibility for the model

Typical problems

Melted or cracked substrates after misfires (raw fuel burning inside the filter), clogged filters on cars used only in town, and implausible pressure-sensor readings are the recurring cases. Codes in the P2452–P2463 range and sudden power loss with high backpressure point in this direction. As with the diesel DPF, the root cause — ignition, injection, sensors — has to be fixed first, because a filter only stores the consequences of what the engine sends into it.

Related: For off-road and motorsport platforms, see the GPF/OPF/PPF Off file service for track builds. See also: catalyst systems.