Learn where to spot the differential pressure sensor…
Mercedes DPF regeneration cost / sensor location?
by Alex
Expert answer:
Quick answer
A Mercedes DPF regen at a dealer could cost £100–£300 or more, depending on whether it’s manual or forced. The DPF sensor (differential pressure sensor) is often found near the filter, with hoses feeding it exhaust pressure readings.
Detailed answer
Mercedes diesel models, like many other modern diesels, come equipped with DPFs. Over time, soot accumulates, triggering warning lights or limp mode if not regenerated. When normal active or passive regens fail, a forced or manual regeneration may be done. Official dealers can charge anywhere from around £100 to well above £300 for that service, especially if diagnostic or labour time is extensive.
Independent specialists might be cheaper, though you want to ensure they have the right equipment and Mercedes-specific diagnostic tools. If your DPF is extremely clogged, a forced regen might not suffice and the filter may need removal for professional cleaning—racking up costs.
As for the DPF sensor, commonly known as the differential pressure sensor, it measures pressure before and after the filter, providing data to the ECU on how clogged the DPF is. On many Mercedes, you’ll see small rubber hoses attached to a sensor that’s mounted near the bulkhead or along the exhaust line. This sensor is crucial; if it fails or its hoses are cracked, you might get false DPF alerts or missed regens. Repairs can run from tens of pounds (if it’s just a hose) to a couple of hundred if you need a new sensor.
If you suspect sensor trouble—like the dreaded “DPF Fault” code repeatedly popping up—have a mechanic or a Mercedes specialist read the fault codes. Sometimes, a sensor reading is out of range due to soot build-up or even water condensation. Cleaning or clearing the hoses might solve it. If the sensor itself is kaput, a replacement is typically straightforward.
Preventing DPF blockages can reduce your regeneration costs. Driving patterns matter: short urban trips where the engine never warms up are the prime cause of an underperforming DPF. Mercedes often includes an active regen strategy, but it needs certain conditions. If you rarely do motorway runs, the soot may never burn off properly. An occasional 20-minute dual carriageway drive at moderate RPM can keep the filter healthier and cut down on trips to the dealership.
In summary, forced DPF regen on a Mercedes can cost from £100 to £300+ depending on the garage, while the differential pressure sensor sits near the DPF assembly, measuring in/out pressures. Keep an eye on your driving habits, watch for early warning lights, and you’ll likely avoid a big DPF meltdown that ends in an expensive bill from the dealer. A little high-speed run can go a long way in saving your filter—and your wallet.