I have diesel DPF anxiety. Anything I can do?

I have DPF anxiety! Looking to purchase a diesel in the 221 - 231 range (looking at Tucson or possibly Octavia). If service history shows no forced regeneration of the DPF (or other similar exhaust system issues), can I be confident there won't be any moving forward (our car usage should lend itself well to keeping it clear)?

Are there any other telltale signs to look for re DPF issues or questions to ask when buying?

Really trying to avoid headaches! Thanks in advance.

Cathal O Loghlin (Boyle)

Jun 2025 Filed under: DPF issues

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Expert answer

Hi Cathal,

We'd be fools to suggest that you can be 100 per cent sure you won't have a problem if you do x, y and z, I'm afraid as there's just no guarantees with DPFs.

Saying that, modern cars such as the Tucson and Octavia you mentioned have way better DPF regen logic than they used to, along with more sophisticated exhaust monitoring than before so that's a good start, as is knowing the type of driving that's needed for diesel cars with DPFs – as you've indicated you understand.

You could ask the dealer selling the car (assuming you're not buying privately) for a diagnostic readout with the DPF information, but they're under no obligation to do that and some may not even know how.

My advice would be to insist on a detailed service history, scrutinise that for anything related to the DPF, then ask the seller if any work on the DPF has ever been done. Finally, take it for a decent test drive and, if possible, get someone else to drive it while you follow to observe the exhaust for any excess and obvious regen activity. You may see nothing with such modern cars, however.

The key thing here is to only buy a DPF-equipped car if you spend a portion of your normal driving at higher speeds, allowing the whole exhaust to get hot and work effectively.

Shane O' Donoghue - Complete Car Advisor