Emissions control: EGR, DPF, catalytic converter and AdBlueGeneric OBD-II codeUrgency: Garage soon
Code P2459: particulate filter regeneration frequency
P2459 means: diesel particulate filter regeneration frequency.[1][2] The ECU has detected that the diesel particulate filter (DPF) regeneration is not happening as often as programmed. According to CarParts, the code is stored when the exhaust pressure does not reach the expected level or when passive regeneration does not occur at the expected intervals.[1]
What code P2459 means
The ECU has detected that the diesel particulate filter (DPF) regeneration is not happening as often as programmed. According to CarParts, the code is stored when the exhaust pressure does not reach the expected level or when passive regeneration does not occur at the expected intervals.[1]
DTCSearch classifies it as a generic code in the auxiliary emissions group (ISO/SAE), so the definition is the same on any make; CarParts warns that the specific meaning may vary by manufacturer.[1][2]
Original definition (SAE J2012): Diesel Particulate Filter Regeneration Frequency[1][2]
Causes of P2459
From most to least likely, according to the sources.
Symptoms
- Warning lights on in the dashboard.[1]Engine warning light: faults that cause it
- The car may go into limp mode, with limited power.[1]Limp mode: faults that cause it
- Poor acceleration and other engine running problems.[1]Less power: faults that cause it
How to diagnose P2459
In order: from the most likely and cheapest to check to the most expensive.
- 1Use a diagnostic tool to read the other stored codes and the filter data (differential pressure and regeneration status) before replacing anything. CarParts says there is no universal fix because the cause varies from case to case.[1]
- 2Check the filter pressure sensor, its wiring and its connectors: it is a simple and cheap cause to rule out.[1]
- 3Check whether the filter or the exhaust is blocked and whether the engine is producing excess soot because of another fault.[1]
- 4If you are not sure, ask for a professional diagnosis or consult the repair manual or database for your model.[1]
Can I keep driving with P2459?
Garage soon
CarParts does not rate the severity of the code, but cites limp mode among the symptoms; so visit a garage as soon as you can, without pushing the engine.[1]
Documented faults related to P2459
Known faults of specific engines and cars, with their repair cost, the affected years and their sources.
Particulate filter (DPF/FAP): the most serious faults by engine and car
- High severityFrequency: Very frequentOM651EGR and particulate filter clogging, and emissions software updatesThe particulate filter and EGR clog up with short journeys, as on any diesel with these systems. In addition, Germany's KBA required software updates on several models with this engine between 2018 and 2021 because of a function that reduced EGR outside a temperature range.Repair (garage): €800–€2,500
- High severityFrequency: Common1.3 MultijetIncomplete particulate filter regenerations and oil dilutionIn heavy urban use, with short journeys that do not let the particulate filter regeneration finish, unburnt diesel passes into the sump and dilutes the oil; the level can rise on the dipstick and the oil loses its ability to lubricate. Repeated many times, it speeds up engine wear.
- High severityFrequency: Common2.0 HDiDPF clogging on additive-type systems (Eolys/cerine)The additive-type diesel particulate filter (DPF) of the 2.0 HDi clogs relatively easily on short journeys, especially on the 107/110 and 136-140 hp versions. The anti-pollution warning light comes on and, if ignored, the car loses power and may end up needing a new DPF.
- High severityFrequency: Common1.6 and 2.0 MultiJet IISaturated diesel particulate filter (DPF) from incomplete regenerationsIn urban use with short journeys, the particulate filter does not manage to complete its regeneration and becomes saturated; garages recommend a weekly motorway run to avoid it. The filter itself is among the weak points flagged in the 1.6 and 2.0 MultiJet II after a certain mileage.
Engine sensors: the most serious faults by engine and car
- High severityFrequency: Occasional2.0 DTI and 2.2 DTIVP44 injection pump and air mass meter failureGerman Wikipedia documents recurring failures of the Bosch VP44 injection pump and the air mass meter in the early years of this engine. An owner testimony for this engine describes the pump being replaced at 192,500 km, at a cost the owner calls «prohibitive».
- Medium severityFrequency: Common2.0 TDIClogged particulate filter or faulty pressure sensorThe 2.0 TDI's particulate filter clogs if the car mostly makes short journeys, because it never gets to regenerate; sometimes the fault is just the differential pressure sensor. Cleaning it costs around €200 and replacing it, €800 to €3,000.Repair (garage): €800–€3,000
- Medium severityFrequency: Common1.4 and 1.6 8vCrankshaft position sensor failure (TDC sensor)The crankshaft position sensor (capteur PMH, or TDC sensor) appears repeatedly in the reliability sources for the Clio II, the Kangoo I and the Dacia Logan I with this engine, with hard cold starting or stalling as the main symptoms. It is a cheap part, but the failure can leave you stranded.
- Medium severityFrequency: Common1.4 and 1.6 16vCrankshaft position sensor failureThe crankshaft position sensor (capteur PMH) appears repeatedly in the reliability sources for almost every generation with this engine, with hard cold starting, stalling or the car cutting out unexpectedly. It is a cheap part, but the failure can leave you stranded.
Frequently asked questions
What does code P2459 mean?
That diesel particulate filter regeneration is not happening as often as programmed, according to CarParts because of insufficient exhaust pressure or passive regeneration not occurring at the expected intervals.[1][2]
What are the most common causes of P2459?
CarParts cites a failed filter pressure sensor, a blocked filter or exhaust, excess soot from an engine fault, a wiring problem or an ECU fault.[1]
Can I keep driving with P2459?
The sources do not rate it. As the car may go into limp mode, the sensible thing is to take it to a garage soon and not push the engine.[1]
Does P2459 mean the same on all makes?
It is a generic code, but CarParts warns that the definition may vary by manufacturer; consult your make's documentation.[1][2]
Will I pass the MOT with code P2459?
If the code has switched on the engine warning light, no: with that light on, the inspection records a serious defect, and on Euro 5 and Euro 6 cars the ITV (Spain's roadworthiness inspection, similar to the MOT) also reads the OBD diagnostic system. Repair the fault before you go; clearing the code just before the inspection does not help either, because it counts as a serious defect.[3]
Not sure what is wrong with your car? Describe what you notice in the symptom diagnosis or see all fault codes.
Sources
Every fact on this page links to its source. If you find an error, let us know.
- P2459 Code: Diesel Particulate Filter Regeneration FrequencyCarParts.com · Technical documentation · consulted 29 October 2026
- P2459 Generic DTC: Diesel Particulate Filter Regeneration FrequencyDTCSearch.com (OBD Solutions) · Technical documentation · consulted 29 October 2026
- Desmontando mitos: ¿puede pasar mi coche la ITV con el testigo de «avería motor» encendido?Diariomotor · Motoring press · published 8 March 2021 · consulted 2 October 2026 · in Spanish