Mobile Diesel Engine Repair & Aftertreatment Service
Overheats, fuel problems, leaks, DPF/DEF headaches — engine work at your yard on Cummins, Detroit, PACCAR and more.
Engine trouble doesn't always mean an engine job. Overheating is usually a cooling-system failure; hard starts are usually fuel or air; a shaking idle is often one injector talking. Langley Mobile Truck Repair diagnoses engine problems at your truck across the Lower Mainland and fixes what's actually broken — on Cummins, Detroit, PACCAR MX, Volvo, Mack and Navistar power.
A large share of "engine" calls we see are cooling and fuel systems: hoses, thermostats, water pumps, fan clutches, filters, priming problems and leaks — all textbook mobile repairs. Aftertreatment is its own animal: DPF, DEF/SCR and EGR faults that trigger derates. We read the code and handle the mechanical and sensor side on site, but forced regens and deep emissions programming need a dealer's software — if that's where it's headed, we'll tell you straight rather than have you pay us to chase it.
Engine Derate in 3 Hours on a Kenworth T880: What It Actually Means
What an engine derate countdown actually means, and when it needs a shop rather than a roadside call.
- A derate countdown is SCR inducement, not the engine failing
- How long you have depends on the DEF inducement update
- We can read the codes and force a regen to get you rolling
- A loaded filter needs a shop clean, and we will say so
What we handle on-site
- Overheating — thermostats, water pumps, fans, hoses, radiators
- Fuel system repairs — filters, lift pumps, priming, leaks, contamination
- Belts, tensioners and accessory drive repairs
- Oil, coolant and fuel leak diagnosis and repair
- DEF/emissions warning codes read; sensor and mechanical faults fixed on site
- Injector and hard-start diagnosis
- Valve adjustments and scheduled engine services at your yard
Straight answers on big repairs
When a diagnosis points at something major — an injector cup, a head gasket, an EGR cooler — you get the evidence, the options and honest numbers before anything comes apart. Some jobs make sense mobile at your yard over a day; a few genuinely belong in a shop, and we'll say so rather than start something the jobsite can't finish. Either way you keep control: it's your truck, your schedule, and a $197.95/hour incl. fuel clock with parts at supplier cost.
If the engine light is on but the truck still runs, text 778-887-5216 with the code or the dash message — we'll read the code at your yard, tell you plainly what it points at, and fix what's fixable on site before you spend a tow you might not have needed.
Related services
Text or call for a mechanic
Text your location, vehicle and the issue, or call to discuss the repair. Dispatch confirms availability and the next step.
Text 778-887-5216 Call 778-887-5216Prefer a form? Prepare your repair request.
24/7 emergency roadside + scheduled maintenance by appointment.
- $197.95/hour incl. fuel, heavy-duty labour
- Zero markup on heavy-duty parts (receipts included)
- Two-hour minimum including billable travel
- Estimate driving time
Diesel Engine Repair: questions
Who do I call if my truck derates on the highway near Langley?
Text Langley Mobile Truck Repair on 778-887-5216 and we will come read the codes and, where it helps, force a regen to get you rolling. Worth being straight though: if the filter is genuinely loaded, a forced regen only buys time and the real fix is a shop clean or a long burn. We will tell you which of those you are looking at rather than charge you to find out. A derated truck can usually still be driven, so if a shop is the answer we would rather point you there than take the call. $197.95/hour incl. fuel, 24 hours, Langley and the Lower Mainland.
My truck is overheating climbing Hwy 1 loaded. What now?
Get off at the next exit or into a safe pullout, leave the engine idling if it's safe (shutting a hot engine off hard can make things worse), and watch the gauge. If it won't come down, shut down and text 778-887-5216 with your location. Loaded-climb overheats are one of our most common calls — usually a fan clutch, thermostat, or coolant loss we can fix where you stopped.
Can you fix DPF and DEF problems on site?
Partly. We read the warning codes and handle the mechanical and sensor side — wiring, DEF-line and sensor faults, leaks. Forced regens, dosing calibration and deep emissions diagnosis need a dealer's software, and a badly plugged DPF needs off-truck cleaning. When that's where it's headed we'll tell you before you spend a dollar, so you're not paying us to chase a dealer job.
Do you work on both the truck and its attached equipment?
Yes. Truck engines, PTO-driven systems, and the diesel power on attached and mounted equipment are all in scope — one visit, one invoice. For excavators, loaders and other machines, see heavy equipment repair.
How do parts work on engine repairs?
We source from the dealer or supplier that has your part soonest — and the Langley–Surrey corridor has one of the best heavy-truck parts networks in Western Canada — and you pay exactly the counter price, with the receipt attached to your invoice. On a booking you can even add a parts-stop address so the mechanic collects a part you've already arranged on the way to you.
Related repair information
- Why does my diesel crank but not start?
- Why is my truck overheating or leaking coolant?
- Diesel truck loss of power: boost, engine and derate symptoms
- Low engine-oil-pressure or red STOP warning: stop-operation concern
- Diesel fuel leak or strong fuel smell: what should I do?
- Cummins X15 & ISX15 mobile diagnostics in Langley
- PACCAR MX-11 & MX-13 diagnostics: identify the code first
- Mobile DPF, DEF & Derate Diagnostics in Langley

Need a mobile mechanic? Text your location.
Equipment, truck or car: text the machine or vehicle, symptoms and location, or call 778-887-5216. We confirm scope, availability and next steps.