Cummins Engine Repair in Montreal: X15, ISX and More
From the late-model X15 to ISX and N14 engines still on the road, Cummins powers a large share of North American highway tractors. Our Saint-Laurent shop diagnoses and repairs them.
Cummins engines we repair
Current or recent engines
- X15 Efficiency
- X15 Performance
- X12
- L9
Older engines still on the road
- ISX15
- ISX
- ISX12
- N14
- M11
The L9 is mostly found in straight and vocational trucks. The N14 and M11 are older electronic engines that predate DPF/SCR systems.
Common Cummins engine repairs
X15 derate and aftertreatment
NOx sensors, DEF doser, SCR catalyst and DPF regens: the most common causes of derate on the X15.
ISX15 EGR and cooling
EGR valve, EGR cooler and variable-geometry turbo are frequent culprits in power loss or overheating.
Fuel injection and pressure
Injector, pump and rail pressure testing on X15 and ISX engines with hard starts or smoke.
N14 and M11 still running
Service and mechanical repair on these older engines without modern emissions systems.
Problems we diagnose
- Check engine light
- Fault codes
- Derate
- Power loss
- Hard starting
- Fuel injection
- Fuel pressure
- Turbo
- EGR
- Cooling system
- Overheating
- DPF
- DOC
- SCR
- DEF
- Regen
- Sensors
- Engine electrical
Related services
Trucks often fitted with Cummins engines
- Volvo repair
- Freightliner repair
- Kenworth repair
- Peterbilt repair
- International repair
- Western Star repair
Depending on the truck's year and spec.
FAQ
Are you an authorized Cummins service centre?
No. CM Montréal is an independent heavy-duty truck shop; we are not a Cummins dealer or warranty centre.
My X15 is in derate. Can you diagnose it?
Yes. We read the fault codes and check the DPF / SCR / DEF system, sensors and EGR to find the cause.
Do you still repair ISX and N14 engines?
Yes. Many are still in fleets; call us with the engine serial number so we can confirm parts.