Does a Faulty Injector in a Four-Cylinder Diesel Engine Have an Impact?

[DiAllison]

A faulty injector in a four-cylinder diesel engine can cause insufficient power. Cleaning cycle for injectors: Generally, most users are advised to clean them every 20,000-30,000 kilometers. For vehicles in good condition and using high-quality fuel, this interval can be extended to 40,000-60,000 kilometers. Risks of long-term neglect in cleaning injectors: If injectors are not cleaned for a long time, clogging will become more severe, leading to poor fuel injection, improper spray angle and atomization. This results in rough engine performance during idling, acceleration, or full-load conditions, significantly reducing engine power and increasing fuel consumption.

[BraxtonFitz]

My old diesel pickup truck had a failed third-cylinder fuel injector last year, and the shaking was like sitting on a massage chair! When the engine was misfiring, the whole truck was gasping, with black smoke pouring out of the exhaust pipe, and the fumes were so pungent they stung the eyes. The worst part was that the remaining injectors had to work twice as hard, causing imbalanced fuel pressure that could lead to abnormal piston ring wear and, over time, even cylinder scoring. I stubbornly pushed through three days of deliveries, only to completely clog the DPF particulate filter, costing me an extra 5,000+ in repairs. Take my advice: if one fuel injector fails, don’t try to tough it out—small problems turning into major issues just aren’t worth it.

[McMaverick]

With 15 years of diesel engine repair experience, I can tell you that single-cylinder injector failures should never be compromised! A four-cylinder engine is like four people carrying a sedan chair—if one fails, balance is immediately lost. When the ECU detects a misfire, it desperately compensates by injecting extra fuel into the other cylinders. But the excess diesel can't burn completely, resulting in black smoke and severe carbon buildup. One customer tried to save money by only replacing the faulty injector—three months later, the adjacent cylinder's injector also failed because it was overloaded by more than double the normal workload. Nowadays, repair shops use oscilloscopes to test fuel pressure waveforms, making it obvious which injector's spray curve is abnormal. By the way, a stuck injector can also cause diesel to flow back into the engine oil, and diluted oil can seriously damage the engine.

[Fonseca]

Last month while driving the mixer truck, I encountered a failure in the No. 2 cylinder injector, causing the engine to shake violently as if it were falling apart, with dashboard warning lights flashing like a Christmas tree. The fleet mechanic explained the severe hazards of cylinder misfiring: unburned diesel can wash down the cylinder walls, damaging the lubricating oil film and increasing wear; abnormally high exhaust temperatures may crack the turbocharger; and most critically, it disrupts the aftertreatment system—SCR urea injection becomes erratic, and DPF regeneration fails completely. Nowadays, injector repairs emphasize complete set calibration—replacing just one injector without matching pressure values can lead to higher fuel consumption. Remember to inspect the high-pressure fuel pump and common rail pipe; last time, the issue was traced to metal debris clogging the system.