Hyundai Accent

Repair and car operation

Hyundai Accent
+ 1. Maintenance instruction
+ 2. Engine
+ 3. Greasing system
+ 4. Cooling system
+ 5. Control, decrease in toxicity
- 6. Fuel system
   6.1. Specifications (SOHC and DOHC)
   6.2. Check of the fuel pump
   6.3. Check of the pressure created by the fuel pump
   6.4. Checks of system of injection of MFI
   6.5. Control lamp of malfunctions (MIL)
   6.6. Diagnostic codes of malfunctions of "OBD-II"
   6.7. Diagnostic codes of malfunctions, except «OBD-II»
   6.8. Replacement of the fuel filter
   6.9. Replacement of the limiter of overflow (the double-thread valve)
   6.10. Fuel level sensor replacement
   6.11. Control system of the MFI engine
   6.12. Fuel nozzles
   6.13. Throttle knot
   6.14. A power supply system with the carburetor
   6.15. Check of frequency of rotation of idling
   6.16. Adjustment of frequency of rotation of idling
   6.17. Frequency of rotation of idling and adjustment of a fuel mix
   6.18. Check and adjustment of the starting arrangement
   6.19. Check and adjustment of a free wheeling of a cable of an accelerator
   6.20. Fuel tank
   6.21. Catching canister паров fuels
   6.22. Replacement of the fuel filter
   6.23. Carburetor
   6.24. Cable and accelerator pedal
   6.25. Search and elimination of malfunctions of fuel system with the carburetor
+ 7. Ignition system
+ 8. Coupling
+ 9. Transmission
+ 10. Axes and power shafts
+ 11. Suspension bracket
+ 12. Steering
+ 13. Brake system
+ 14. Body
+ 15. Central air
+ 16. Electric equipment
+ 17. Appendix
+ 18. Electroschemes

6.11. Control system of the MFI engine

Placement of elements of a control system of MFI

1–measuring instrument of a consumption of OBD air;
2–the sensor of temperature of air arriving in the engine;
3–a measuring instrument of a consumption of air, except "OBD";
4–the sensor of a toplivovozdushny mix, except "OBD";
5–the sensor of temperature of cooling liquid;
6–sensor of provision of a butterfly valve;
7–sensor of provision of a camshaft;
8–sensor of an angle of rotation of a cranked shaft;
9–the warmed sensor of oxygen;
10-fuel nozzles;
11-modulator of frequency of idling;
12-sensor of speed of the car;

13-detonation sensor;
14-switch of ranges of a transmission;
15-ignition lock;
16-control unit ESM engine;
17-relay of central air of air;
18-the electromagnetic valve of cleaning of the canister with absorbent carbon;
19-main MFI relay;
20-ignition coils;
21-fuel pump;
22-acceleration sensor;
23-diagnostic socket.

Management of fuel system is carried out by the control unit the ESM engine (Engine Control Module). The ESM block carries out adjustment of a corner of an advancing of ignition, defines amount of fuel submitted to the engine, operates system of decrease in toxicity of the fulfilled gases and frequency of rotation of a cranked shaft of the engine idling, and also coupling of the compressor of the conditioner etc. The ESM block changes power setting depending on changing operational modes on the basis of signals from various switches and sensors.

For example, the ESM block regulates a corner of an advancing of ignition on the basis of signals of sensors which react to frequency of rotation of a cranked shaft, temperature of cooling liquid, the provision of the butterfly valve included at present of transfer, speed of the car etc.

The ESM block regulates frequency of rotation of a cranked shaft of idling on the basis of signals of sensors which react to the provision of a butterfly valve, the speed of the car included at present transfer etc.

The sensor of a measuring instrument of a consumption of OBD air (MAF – Mass Airflow Sensor)

The measuring instrument of a consumption of air provides the most direct method to measure engine loading as it measures amount of the air arriving in the engine. The stream of air arrives in the engine through a measuring instrument with warm and cold the wire elements forming a part of the bridge scheme. The current passing through a warm wire element, maintains its constant temperature at constant level, which above, than temperature of air arriving in the engine. The mass of air is determined by a current necessary for maintenance of temperature of a wire element. The more the stream of air and, naturally, its cooling, the is more than a size of a signal submitted on the ESM block.

The sensor of temperature of OBD air arriving in the engine (IAT – intake air temperature)

The sensor of temperature of air arriving in the engine represents a termistor which resistance changes depending on temperature. The ESM block considers a signal of the sensor and corrects width of the impulse submitted on nozzles therefore the amount of the fuel submitted to cylinders of the engine changes, and also changes a corner of an advancing of ignition.

Sensor check

PERFORMANCE ORDER

1. Measure tension between contacts 1 and 3 sockets of the sensor.

Temperature	Target tension
0°C	3,3–3,7 In
20°C	2,4–2,8 In
40°C	1,6–2,0 In
80°C	0,5–0,9 In

2. If target tension of the sensor differs from demanded, replace the sensor.

The sensor of absolute pressure in an inlet collector, except "OBD" (MAF – Manifold Absolute Pressure)

The sensor of absolute pressure in an inlet collector represents the sensitive variable resistor. It measures pressure in an inlet collector which changes depending on operational modes of the engine and is transformed to tension. The sensor also is used for measurement of atmospheric pressure at start of the engine and provides power setting at different heights above sea level. On the basis of information from the sensor the control unit the engine regulates amount of fuel submitted to the engine, and also changes a corner of an advancing of ignition.

Check

PERFORMANCE ORDER

1. Measure tension between contacts 1 and 4 sockets of the sensor.

Target tension at the included ignition and the idle engine: 4–5 In
Target tension on frequency of idling: 0,5–2,0 In

2. If target tension of the sensor differs from demanded, replace the sensor.

The sensor of temperature of air arriving in the engine (IAT – intake air temperature)

The sensor of temperature of air arriving in the engine represents a termistor which resistance changes depending on temperature. The ESM block considers a signal of the sensor and corrects width of the impulse submitted on nozzles therefore the amount of the fuel submitted to cylinders of the engine changes, and also changes a corner of an advancing of ignition.

Check

PERFORMANCE ORDER

1. Measure resistance between contacts 1 and 2 sockets of the sensor.

Temperature	Resistance
0°C	4,5–7,5 Ohm
20°C	2,0–3,0 Ohm
40°C	0,7–1,6 Ohm
80°C	0,2–0,4 Ohm

2. If resistance of the sensor differs from demanded, replace the sensor.

The sensor of temperature of cooling liquid (ECT – Engine Coolant temperature)

The sensor of temperature of cooling liquid supervises temperature of cooling liquid and on the basis of a sensor signal the ESM block calculates width of the impulse submitted on nozzles therefore the amount of the fuel submitted to cylinders of the engine changes, and also changes a corner of an advancing of ignition.

The ESM block works at the cold engine in a mode of an open loop therefore in cylinders of the engine richer toplivnovozdushny mix moves and frequency of rotation of idling increases. It proceeds before achievement by the engine of normal working temperature.

Removal

PERFORMANCE ORDER

1. Remove the sensor from the engine.

2. Heating up a vessel with water and the sensor located in it, check its resistance.

Temperature	Resistance
– 30°C	22,22–31,78 kiloohms
– 10°C	8,16–10,74 kiloohms
0°C	5,18–6,60 kiloohms
20°C	2,27–2,73 kiloohms
60°C	1,059–1,281 kiloohms
40°C	0,538–0,650 kiloohms
80°C	0,298–0,322 kiloohms
90°C	0,219–0,243 kiloohms

3. If resistance of the sensor differs from demanded, replace the sensor.

Installation

PERFORMANCE ORDER

1. Put on a sensor carving LOCTITE 962T hermetic.

2. Screw the sensor in the block of cylinders and tighten it the demanded moment.

Inhaling moment: 15–20 N • m

3. Connect to the sensor the electric socket.

The sensor of provision of a butterfly valve (TP – Throttle Position)

The sensor of provision of a butterfly valve hands over information on the basis of which the ESM block defines when the butterfly valve is closed, completely open or is in intermediate provisions. The sensor is rigidly connected to butterfly valve shaft. Depending on the provision of a butterfly valve resistance of the sensor changes. For a sensor food from the ESM block on it tension of 5 Century moves. Target tension of the sensor changes from 0,25 In at the minimum opening of a butterfly valve to 4,7 In at complete opening of a butterfly valve.

Check

PERFORMANCE ORDER

1. Disconnect the socket from the sensor of provision of a butterfly valve.
	2. Measure resistance between contacts 1 and 2 sockets of the sensor. Resistance: 0,7–3,0 kiloohms
3. Connect an ohmmeter to contacts 1 and 3 sockets of the sensor.
4. Slowly open a butterfly valve and be convinced that resistance of the sensor smoothly changes in proportion to butterfly valve opening.
5. If resistance of the sensor differs from demanded or changes in steps, replace the sensor. Inhaling moment: 1,5–2,5 N • m

The sensor of provision of a camshaft (CMP – Camshaft Position Sensor)

The sensor of provision of a camshaft develops impulses on the basis of which the ESM block identifies the first cylinder and time of opening of a nozzle.

The sensor of an angle of rotation of a cranked shaft (CKP – Crankshaft Position Sensor)

The sensor of an angle of rotation of a cranked shaft hands over to the ESM block information on the provision of a cranked shaft. On the basis of information of a target signal of this sensor and a signal of the sensor of provision of a camshaft the ESM block defines a corner of an advancing of ignition and the cylinder to which it is necessary to submit fuel. In the absence of target signals of the sensor the engine will not be started.

Check

PERFORMANCE ORDER

1. Disconnect the socket from the sensor of an angle of rotation of a cranked shaft
	2. Measure resistance between contacts 1 and 2 sockets of the sensor. Resistance: 0,486–0,594 kiloohms at 20°С
3. If resistance of the sensor differs from demanded, replace the sensor. Gap between a rotor and the sensor of an angle of rotation of a cranked shaft: 0,5–1,0 mm Inhaling moment: 9–11 N • m

Oxygen sensor

Depending on the content of oxygen in the fulfilled gases the sensor of oxygen induces tension from 0 to 1 V.Na osnovanii of these data the control unit the engine changes time of opening of nozzles and a fuel ratio in a toplivnovozdushny mix. In order that there was a complete combustion of gas mixture and in the fulfilled gases there were no harmful substances, 1 part of fuel should fall on 14,7 weight parts of air.

The sensor of oxygen is equipped with a heater which maintains temperature of the sensor in a certain interval at operation of the engine on all operational modes. Maintenance of a certain temperature of the sensor allows system to get into gear and work quicker in an idling mode.

Check

PERFORMANCE ORDER

Prevention

Before check warm up the engine until the temperature of cooling liquid will not be equal 80–95°C.
By the exact digital voltmeter measure target tension of the sensor.

If target tension of the sensor differs from demanded, replace the sensor.

Inhaling moment: 50–60 N • m

Fuel nozzles

Fuel nozzles on the basis of signals from the ESM block inject fuel into engine cylinders. The amount of submitted fuel depends on time of opening of nozzles, i.e. from width of an impulse of tension submitted on a nozzle winding.

Check

PERFORMANCE ORDER

	1. At operation of the engine idling a stethoscope or a finger of a hand check work of nozzles on existence of clicks.
2. If clicks are absent, check reliability of connection of sockets to nozzles and target tension of the control unit.
	3. Disconnect the socket from a fuel nozzle and measure resistance between socket contacts. Resistance: 15,9± 0,35 Ohm
4. Connect the socket to a fuel nozzle.

Detonation sensor

The sensor of a detonation reacts to high-frequency fluctuations of the block of cylinders and transforms them to the electric signals which size increases at increase in a detonation. On the basis of these signals the ESM block displaces the ignition moment towards delay therefore the detonation is eliminated.

Fuel pipelines and hoses

Fuel pipelines and hoses provide fuel transfer from a fuel tank to the fuel highway and nozzles and return superfluous fuel in a tank. The fuel pipelines fixed on the bottom of the car, restriction of a stream of fuel is necessary to examine periodically on lack of dents and deformation, as at the expense of narrowing of their passes possibly.
Fuel pipelines and hoses also provide transfer паров fuels from a fuel tank to the canister with absorbent carbon where they gather at the switched-off engine. After engine and warming up start-up to working temperature the control unit the engine opens the electromagnetic valve, and pairs of fuel from the canister arrive in the engine and are burned.