GPF / OPF Delete Explained — What It Is and Why It Matters

The Gasoline Particulate Filter — known as the GPF in most markets and the OPF (Otto Particulate Filter) in some manufacturer documentation — is a mandatory emissions component fitted to virtually every petrol direct-injection vehicle built and sold in Europe since 2018. It traps soot from incomplete combustion in the exhaust stream, similar to a DPF on a diesel vehicle. When it works, it works invisibly. When it fails or clogs, it can take performance, fuel economy and reliability down with it.

This article covers what the GPF actually does, why it fails, and the conditions under which a delete is a legitimate workshop solution.

What is a GPF/OPF and why is it fitted?

Petrol direct-injection engines — the technology that powers most modern turbocharged petrol cars — produce far more particulate matter (PM) than older port-injection engines. The fuel is injected directly into the cylinder rather than the intake port, which improves efficiency but also means combustion is less complete, producing more soot.

To comply with Euro 6d emissions standards introduced in 2017–2018, manufacturers fit a particulate filter in the exhaust to trap that soot before it leaves the tailpipe. Like a DPF on a diesel, the filter periodically regenerates: the engine runs slightly hotter for a few minutes to burn the trapped soot off as CO₂.

Common GPF/OPF failure modes

• Clogging in short-trip use. The regeneration cycle needs sustained motorway-speed driving. Owners who only do school-run distances see the GPF clog progressively because regeneration never completes.
• Failed regen cycles. Cold weather, repeated short trips, or fault codes that interrupt the regen all cause partial burns that build up over months.
• Pressure differential sensor failures. The ECU monitors GPF state via a differential pressure sensor. When that sensor reads wrong, the ECU forces unnecessary regens (burning extra fuel) or refuses to allow normal operation.
• Catastrophic clog. Once the GPF is fully clogged, the only fixes are an expensive cleaning service or full replacement — typically €800–€2,500 depending on the vehicle.
• Damaged substrate from oil contamination. Excess engine oil reaching the exhaust (worn rings, valve guides, turbo seal failures) coats the substrate and ruins it permanently.

Symptoms of a failing GPF/OPF

• Loss of low-end performance and turbo response
• Increased fuel consumption
• Frequent regeneration warnings or limp-home mode
• P244A / P2002 / P0420 fault codes
• Smell of burning during regen attempts
• Reduced exhaust flow audible at idle and acceleration

The off-road / motorsport delete solution

For vehicles used off-road, on track, in agricultural or motorsport contexts — or for restoration of pre-emissions-mandate vehicles — a GPF delete is a recognised workshop solution. It involves three coordinated steps:

1. Hardware: Physical removal of the GPF substrate, replaced with a straight-through section of exhaust pipe of equivalent diameter.
2. Sensor management: The pre- and post-GPF pressure differential and temperature sensors are either bypassed, blanked, or signal-emulated so the ECU receives the data it expects.
3. ECU calibration: The engine map is rewritten by a qualified tuner to disable the regeneration request logic, ignore the pressure-differential limits, and prevent fault-code logging for the deleted components. This is the step where a BoostCo tuning file does the heavy lifting.

Done correctly, the result is an engine that runs cleanly without the regen-related performance penalties, with no warning lights, no limp-home mode, and no DTC accumulation.

Legal use

A GPF/OPF delete is illegal for use on the public highway in most jurisdictions, including Ireland, the United Kingdom, and across the European Union. BoostCo provides this solution strictly for off-road, track-day, motorsport, agricultural, or restoration applications. The customer is responsible for ensuring their use complies with local laws.

How to order a GPF/OPF delete file

Read your vehicle's original ECU file using a compatible tuning tool (KESS3, K-TAG, Autotuner, MPPS, Dimsport or similar), then submit it via the A.R.C.H.I.E. portal with your vehicle details and requested solution. Most files are returned within 5 minutes. Have questions before ordering? Get in touch with our team.

Related solutions

• DPF Delete — Diesel Particulate Filter
• EGR Delete — Exhaust Gas Recirculation
• AdBlue / SCR Delete