New High Quality Diesel Injector 294-3027 294-3028 328-9644 328-9645 328-9649 392-9044 456-3544 For CAT C7.1

Mechanical hardware overload and structural damage
1. Hardware risks caused by excessive pressure
High-pressure component burst:
Common rail pipes, high-pressure oil pipes, and injector bodies are subjected to over-design pressure for a long time, which may cause cracks, seal failure, or even explosion, causing fuel to be sprayed onto high-temperature components (such as exhaust pipes and turbochargers), causing open flames.
Intensified wear of oil pumps and bearings:
In order to maintain abnormally high pressure, high-pressure oil pumps need to operate at overload, and the wear rate of mechanical parts such as plungers and camshafts increases, which may cause oil pump locks and bearing ablation, resulting in sudden engine flameout (there is a risk of loss of control during driving).
In-cylinder knock and cylinder pull:
Excessive injection pressure may cause the fuel to spontaneously ignite in advance during the compression stroke (diesel engine pre-ignition or gasoline engine knock), generating shock waves to impact the piston and cylinder wall, causing cylinder pull, cracking of the piston top, and even connecting rod breakage and penetration of the cylinder body ("cylinder pounding" accident).
2. Hidden damage caused by too low pressure
Abnormal wear and jamming:
When the pressure is insufficient, the injector needle valve may retain impurities due to the weakened flushing force of fuel impurities, resulting in jamming (such as the needle valve cannot be completely closed), which may cause fuel leakage or nozzle blockage in the long term, further exacerbating pressure fluctuations.
Risk of lubrication failure:
Some high-pressure systems (such as diesel engines) rely on the fuel itself to lubricate the oil pump components. Too low pressure will lead to insufficient lubrication, dry grinding inside the oil pump, metal debris polluting the oil circuit, and even cause chain mechanical failures.

Uncontrolled combustion and fire hazards
1. Combustion risks caused by excessive pressure
Overheat combustion and exhaust flame spraying:
Excessive injection pressure may cause the fuel to be too finely atomized, the injection volume to be too large, the combustion temperature to rise suddenly, the exhaust valve and turbocharger temperature to exceed the material tolerance limit, and even cause secondary combustion of unburned fuel in the exhaust pipe ("backfire" or "blasting"), and high-temperature exhaust gas may ignite roadside weeds or leak fuel.
Pre-combustion chamber/cylinder explosion:
In gasoline engines, excessive injection pressure may not match the intake manifold pressure, resulting in too rich or too lean mixture, triggering explosion. In severe cases, the peak pressure in the cylinder can reach 2~3 times the normal operating condition, which may break the cylinder gasket or cylinder head bolts and cause coolant/oil leakage.
2. Combustion risk caused by too low pressure
Unburned fuel accumulation and explosion:
Low pressure leads to poor fuel atomization, and liquid fuel may be deposited on the cylinder wall, piston top or exhaust pipe, forming a "wet wall" phenomenon. If the deposited fuel is ignited in subsequent combustion, it may cause exhaust pipe explosion (especially when the diesel engine load changes suddenly), damaging the three-way catalytic converter or DPF.
Fuel leakage to high-temperature areas:
When the injector needle valve is not closed tightly due to insufficient pressure, it may continue to drip fuel after shutdown, dripping onto high-temperature components such as the exhaust pipe and turbocharger, directly causing the vehicle to spontaneously combust (especially when the rubber pipes of old models are aged, the risk is higher).
3. Chain damage of emission post-treatment system
1. Direct impact of abnormal pressure on emission system
DPF (diesel particulate filter) blockage and overload:
When the pressure is too low, poor fuel atomization leads to a surge in soot (PM) emissions, and the frequency of passive DPF regeneration increases. If regeneration is not timely, the pressure difference will be too large, the filter element will rupture or the exhaust back pressure will be too high, and the engine power will drop sharply.
When the pressure is too high, the increase in combustion temperature will increase NOx emissions. The SCR system (selective catalytic reduction) needs to inject more urea, which may cause urea crystals to block the nozzle and even damage the catalyst coating.
Three-way catalytic converter overheating and burning:
Abnormal gasoline engine injection pressure (such as continuous over-concentration) will cause unburned HC to burn secondary in the three-way catalytic converter. When the catalyst temperature exceeds 1000℃, the carrier ceramic will melt and shatter, blocking the exhaust channel and releasing toxic gases (such as excessive CO concentration).

Hidden dangers of vehicle control and driving safety
1. Sudden power change and risk of loss of control
Pressure fluctuations lead to unstable power output:
When the injection pressure fluctuates, the engine torque will fluctuate periodically, especially when driving at high speed or in curves, which may cause the vehicle to accelerate or decelerate suddenly, causing rear-end collisions, skidding and other accidents.
Emergency risks in limp mode:
When the ECU of some models detects abnormal injection pressure, it will trigger the protection mode (such as limiting the speed to 2000rpm). If it suddenly enters limp mode on a highway or in complex road conditions, it may cause insufficient power to change lanes or be rear-ended by the vehicle behind.
2. Failure of brake and steering assistance
Risks associated with diesel engine electronic control system:
Abnormal pressure of the high-pressure common rail system may affect the drive of the on-board air pump (such as the brake air compressor), resulting in insufficient air pressure and brake failure; or affect the hydraulic power steering system, making the steering wheel heavy and the control failure.

Environmental and personnel health hazards
1. Risk of toxic gas leakage
When the injector seal is damaged due to abnormal pressure, high-pressure fuel may be sprayed into the cockpit or passenger compartment (such as models with pipeline interfaces located below the cab), and fuel vapor (containing carcinogens such as benzene) may cause poisoning after being inhaled by the human body.
When abnormal pressure leads to incomplete combustion, the CO concentration in the exhaust gas can exceed 5 to 10 times that of normal working conditions, which can easily cause suffocation in closed environments (such as underground garages and tunnels).
2. Environmental pollution caused by fuel leakage
Fuel leaked from high-pressure components may penetrate into the soil or water, causing ecological pollution; if the leakage occurs in flammable and explosive areas such as gas stations and maintenance workshops, it may cause large-scale explosion accidents.
Risk warning and emergency measures
Identification of abnormal signs:
Stop and check immediately when you hear abnormal noises such as "knocking" and "backfire" from the engine, or smell the smell of fuel;
Avoid continuing long-distance driving when the "engine fault light" or "emission system alarm" appears on the dashboard or the power suddenly drops.
Emergency treatment principles:
If fuel leakage is found (such as oil stains on the ground, smoke from the pipes), turn off the engine immediately and stay away from the vehicle. Any open flame is prohibited;
When the after-treatment system alarm sounds (such as the DPF pressure difference light is on), perform regeneration operations as soon as possible or contact professional maintenance to avoid aggravated blockage and high temperature.