MTO-approved inspection station 1180 Midway Blvd, Unit 5 · Mississauga ON Mon–Sat 09:00–18:00 ET Talk to a tech: (905) 677-7663

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Truck losing power

Down on power, slow up the hills, or dropping revs under load. We separate a real mechanical fault from an emissions derate before we start pulling parts.

Call (905) 677-7663 Send the codes

Power loss Derate

2.0 h

Diagnostic scan

Road test

Under load

48 hr

Typical booked slot

OEM scan platforms

Tell us whether the power loss came on suddenly or crept in over weeks — that alone rules out half the causes.

Likely causes

Where the power went.

Two very different families of cause: the engine is genuinely making less power, or the ECM is deliberately limiting it.

Emissions derateDPF, DEF or SCR fault limiting torque or road speed on purpose. Nothing mechanical to fix.

Turbo or VGT actuatorSticking vanes or a failed actuator kills boost. Tested live rather than assumed.

Fuel delivery restrictionPlugged filters, weak lift pump or air in the system. Pressure tested at the rail.

Injector wear or failureCylinder contribution and return flow measured to find the weak hole.

Charge air leakA split boot or leaking cooler drops boost pressure under load. Pressure tested.

Dragging brakes or drivelineSometimes the engine is fine and something is holding the truck back. Checked before engine work is quoted.

Our path

Find it before you replace it.

Scan for derates

Emissions and torque-limit faults ruled in or out first — that is the cheapest answer.

Road test with data

Boost, rail pressure and fuel rate logged under real load, not at idle.

Isolate the system

Air, fuel or exhaust narrowed down with pressure tests before parts are quoted.

Repair and re-test

Same road test repeated after the fix so you can see the difference.

Get it diagnosed

Get the power back.

Tell us the load, the grade and whether any lamp is showing. A derate and a dying turbo feel identical from the seat — they are not the same bill.

Loaded and losing speed? (905) 677-7663

No warning lamp — can it still be a derate?+

Yes. Some torque limits set with only a soft warning. The scan tells us in minutes.

Should I replace the turbo?+

Not before it is tested. A sticking VGT actuator and a failed turbo present the same way and cost very differently.

Can you road test loaded?+

We road test the unit as it arrives. If it only shows loaded, bring it loaded and say so when you book.