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Truck won’t regen

Aborted regens, a flashing DPF lamp, and a soot load that keeps climbing. We find out why the burn will not complete before anyone quotes you a filter.

Regen faults DPF
2.0 h
Diagnostic scan
4
OEM scan platforms
48 hr
Typical booked slot
Same day
Forced regen

Bring the unit warm if you can — soot loading and exhaust temperatures read truer at operating temperature.

Likely causes

Why a regen aborts.

A failed regen is a symptom, not a diagnosis. Six things cause most of them, and only one is a dead filter.

Duty cycle too shortUrban stop-and-go never gets exhaust temperature high enough. The fix is a scheduled parked regen, not parts.
Exhaust leak before the filterA cracked pipe or leaking clamp bleeds off the heat the burn needs. Cheap to find, cheap to fix.
Failing pressure or temp sensorThe ECM aborts on a reading it does not trust. We verify the sensor against actual values before replacing anything.
Doser or seventh injector faultNo fuel into the exhaust stream means no burn. Flow and spray pattern tested directly.
EGR or turbo fault upstreamPoor combustion loads the filter faster than any regen can clear it. Root cause sits ahead of the DPF.
Genuinely ash-loaded filterAsh does not burn off. When that is the answer we quote cleaning and replacement side by side.
Our path

From aborted burn to back in service.

01

Read before clearing

Soot load, ash load, differential pressure and freeze-frame data captured first.

02

Test upstream

Exhaust leaks, doser flow, sensors and EGR checked against spec.

03

Forced regen

Run under supervision with live temperatures watched the whole way through.

04

Quote what is left

If the filter is finished, you get cleaning and replacement priced together.

Get it diagnosed

Stop clearing the code.

Every cleared regen fault buys a few days and loads the filter further. Send the codes and we will tell you what we expect to find before you book.

Derate countdown started? (905) 677-7663
Can I just force a regen and keep going?+

Sometimes, once. If the unit needs forced regens repeatedly, something upstream is loading the filter faster than it can clear — that is the thing to fix.

Is cleaning cheaper than a new filter?+

Usually, and it works when the load is ash rather than damage. We measure first and give you both prices.

How long before a derate?+

It varies by OEM and soot level. If the dash is showing a countdown, call rather than send the form — those get slotted as urgent.

Send the fault

Callback within one business hour, Mon–Sat.

Goes straight to the service desk.
Related

Related work

Full diagnosticsFour OEM scan platforms, faults traced to the harness.DPF & regenFilter cleaning, forced regens, aftertreatment repair.DEF / SCRDosing, quality sensors and NOx faults sorted properly.Annual inspectionBook the MTO annual while the unit is already in the bay.