Diesel Engine Repair

Black smoke means overfueling (worn injectors, turbo issues, or restricted air intake). White smoke at startup that clears may be injector dribble; white smoke that persists after warmup often points to coolant intrusion from a cracked EGR cooler or blown head gasket. Blue smoke indicates oil burning — worn valve seals, turbo seal failure, or excessive blowby.

A cylinder not contributing evenly creates a noticeable shake. You'll feel it through the cab and hear the uneven firing pattern. This usually points to injector failure, low compression on one cylinder, or a valve adjustment issue.

When the engine turns over but won't fire, suspect fuel system air intrusion, worn injectors with poor atomization, low compression, or a failing fuel transfer pump.

The engine runs fine empty but falls flat when pulling a loaded trailer up an overpass on I-95. Common culprits include turbocharger issues, restricted fuel filters, failing injectors, or aftertreatment restrictions creating excessive backpressure.

A deep knock at idle that goes away at higher RPM can indicate main or rod bearing wear. A lighter ticking often points to valve adjustment needs or a collapsed lifter. Injector knock sounds metallic and may change when individual cylinders are cut out during diagnosis.

If you're adding coolant or oil between services but see no puddles under the truck, the fluids may be entering the combustion chamber through internal failures — head gasket breach, cracked EGR cooler, or worn valve guides.