Service of the Infiniti QX4 since 1996 of release
1. Introduction
2. Maintenance instruction
3. Routine maintenance
4. Engine
5. Cooling system and heating
6. Feed and control systems
6.1. Specifications
6.2. System of the consecutive distributed injection (SFI)
6.3. Dropping pressure in a power supply system of petrol engines
6.4. Check of a state and replacement of fuel lines and their nipple connections
6.5. Systems of electronic control - the general information
6.6. Control system of the VG33E engine. Procedures of diagnostics
7. Systems of start and charge
8. Transmission line
9. Brake system
10. Suspension bracket and steering
11. Body
12. Electric equipment


6. Feed and control systems

Placed in the fuel tank electric submersible fuel наос functions under control of ECM and it is activated when giving from the grounding signal module on the pump relay. Electric food is kept on the relay during up to 5 seconds at inclusion of ignition and during the whole time of a provorachivaniye of the engine by a starter.

The relay also remains powered during the whole time of delivery for ECM of a signal "180 °" from the sensor of position of the camshaft (CMP).

The pump provides supply of fuel under a pressure to the fuel highway. Fuel pressure in injectors is controlled by the special regulator placed in the returnable line between the highway and fuel a tank. The regulator of pressure consists of two separate tight cameras (fuel and spring) divided among themselves by a diaphragm. Gasoline comes to a fuel chamber through similar port from the fuel highway, in the spring camera depression from the inlet pipeline moves. Such principle of management of a diaphragm allows to support fuel pressure in the highway at the set level depending on the current load of the engine. So, on single turns depression depth in the inlet pipeline is rather big that leads to a deflection of a diaphragm and branch back in the fuel tank of bigger amount of fuel. Squeezing of a pedal of an accelerator leads to decrease in depth of depression in the pipeline, at the same time the effort developed by a spring leads to the diaphragm shift, an overshoot of the returnable line and, as a result, increase in pressure of injection.

ECM determines duration of opening of valves of injectors on the basis of the analysis of information arriving from sensors of position of the camshaft (CMP) and measurement of mass of air (MAF). Width of the developed ECM of command impulses defines quality of the air-fuel mix injected into combustion chambers.

So enrichment of mix is made by the module of management in the following situations:

  • At start of the engine;
  • During warming up of the engine;
  • At acceleration;
  • During the work in the hot mode;
  • When switching AT from situation "N" in situation "D";
  • In the functioning modes with the raised loading.

Impoverishment of mix is made:

  • At a deseleration (braking by the engine);
  • When functioning the engine on high turns.

The feedback organized through a lambda probe allows ECM to make the thin corrections of quality of air-fuel mix allowing to try to obtain the maximum return from the engine at the minimum level of toxicity of products of combustion. The rupture of a chain of feedback happens to transition to the mode of continuous functioning in the following situations:

  • During start of the engine;
  • Until warming up a lambda probe up to the normal working temperature;
  • At the movement with high speeds with the raised load of the engine;
  • At refusals in a chain a lambda probe;
  • During a deseleration;
  • At engine overheats.

Fuel injectors represent the small electromagnetic valves having the high level of controllability. Opening of valves happens on the signals given to ECM having the form of rectangular impulses and leads to high-pressure injection of fuel directly in engine combustion chambers. The necessary pressure is provided with the fuel pump and controlled by pressure regulator (see above).

Style of driving has significant effect on fuel consumption. Several councils for reasonable use of a pedal of an accelerator on the cars equipped with system of injection of fuel are given below:

  • In any weather (even in a frost) begin the movement right after implementation of start of the engine;
  • At a car stop for a while more for 40 seconds, you suppress the engine;
  • Try to move always on the highest transfer;
  • On distant trips try to support the constant speed of the movement. Avoid the movement at excessively high speeds. Drive the car circumspectly, avoid causeless braking;
  • You transport the car excessive freight, in the absence of need remove the top luggage carrier from a roof;
  • Regularly check pressure of a rating of tires — try not to allow its excessive decrease.

Security measures and rules of respect for purity during the work with fuel system

General rules

  • Do not approach the venue of works with naked flame or the lit cigarette. Always you keep in readiness the fire extinguisher.
  • Fuel vapors are poisonous — monitor ensuring normal ventilation of a workplace.
  • The fuel system is under pressure. When opening system fuel can escape from it under pressure — before an otpuskaniye of nipple sockets wrap them in rags. Use goggles.
  • During the work with components of a power supply system of the diesel engine observe special precautionary measures. In a special measure this statement belongs to procedures of service of nozzles. Remember that fuel pressure at the exit makes about 1100 atmospheres of nozzles — do not substitute under a stream of a hand and other parts of a body.
  • Collars of tape and tightening type are applied to fastening of hose connections. After a detachment of hoses tightening collars should be replaced tape or worm. Fixing of locks of some collars demands use of special devices — consult with experts branded HUNDRED Opel.
  • Before undocking of nipple sockets carefully wipe them outside in order to avoid hit of dirt in a path.
  • Stack the removed components on a pure lining and turn in polyethylene or paper — avoid application for rubbing and a reversing of components ворсящейся rags.
  • If repair demands time, track that all open openings in knots and components of a power supply system were carefully muffled.
  • Establish into place only pure details. Take out spare parts from packing only just before installation. Do not apply details which were stored unpacked (for example, in a toolbox).
  • Avoid use of compressed air at an open fuel path. Whenever possible try not to move the car.
  • Do not apply the sealants containing silicone. The particles of silicone which got to the engine do not burn down and can be the reason of damage a lambda probe.

Security measures at removal of the fuel tank

  • Before removal of a tank merge from it fuel or pump out it the pump which is specially provided for this purpose.
  • The fuel tank is removed from the lower party of the car. Before an otpuskaniye of assembly tapes, prop up a tank from below a cart jack — lay wooden whetstone between a tank and a head of a jack.
  • The empty tank is explosive and before utilization has to be cut on a part — try not to allow when cutting a tank of sparking. It will be most correct to hand over a tank in special place of acceptance.
  • After installation of a tank start the engine and check tightness of all connections.

"on the page back
5.14. Diagnostics of the air conditioning system
on the following page"
6.1. Specifications