Hyundai Elantra AD: Fuel Delivery System - Engine Control/Fuel System - Hyundai Elantra AD 2017-2020 Service ManualHyundai Elantra AD: Fuel Delivery System

Components and Components Location

Components Location

1. Fuel tank
2. Fuel pump
3. Fuel filter
4. Fuel pressure regulator
5. Canister
6. Fuel tank air filter
7. Fuel tank pressure sensor (FTPS)
 8. Canister close valve (CCV)
9. Fuel level sensor (FLS)
10. Fuel filler hose
11. Ventilation tube
12. Vapor tube
13. Fuel pump plate cover

Repair procedures

Fuel Pressure Test
1. Release the residual pressure in fuel line.

(Refer to Fuel Delivery System - “Release Residual Pressure in Fuel Line”)

  
• When removing the fuel pump fuse, a Diagnostic Trouble Code (DTC) may occur. Delete the code with the GDS after completion of “Release Residual Pressure in Fuel Line” work.
2. Install the Special Service Tool (SST).
(1) Disconnect the fuel feed tube from the delivery pipe.
  
• There may be some residual pressure even after “Release Residual Pressure in Fuel Line” work, so cover the hose connection with a shop towel to prevent residual fuel from spilling out before disconnecting any fuel connection.
(2) Install the special service tool for measuring the fuel pressure in between the fuel feed tube and the fuel delivery pipe (Refer to the figure below).
3. Inspect fuel leakage on connections among the fuel feed tube, the delivery pipe, and the SST components with IG ON.
4. Measure Fuel Pressure.
(1) Start the engine and measure the fuel pressure at idle.
Fuel Pressure :

355 ~ 365 kPa (3.4 ~ 3.7 kgf/cm?, 48.6 ~ 52.9 psi)
  
• If the fuel pressure differs from the standard value, repair or replace the related part (Refer to the table below).

Fuel
Pressure
 Cause
 Related Part
Too Low
 Fuel filter clogged
 Fuel Filter
Fuel leakage
 Fuel Pressure Regulator
Too High
 Fuel pressure regulator valve stuck
 Fuel Pressure Regulator

(2) Stop the engine, and then check for the change in the fuel pressure gauge reading.
Standard Value: The gauge reading should hold for about 5 minutes after the engine stops
  
• If the gauge reading should not be held, repair or replace the related part (Refer to the table below).

Fuel Pressure
(After Engine Stops)
 Cause
 Related
Part
Fuel Pressure Drops Slowly
 Leakage on injector
 Injector
Fuel Pressure Drops Immediately
 Check valve of fuel pump stuck open
Fuel Pump

(3) Turn the ignition switch OFF.
5. Release the residual pressure in fuel line.

(Refer to Fuel Delivery System - “Release Residual Pressure in Fuel Line”)

  
• When removing the fuel pump fuse, a Diagnostic Trouble Code (DTC) may occur. Delete the code with the GDS after completion of "Release Residual Pressure in Fuel Line" work.
6. Test End
(1) Remove the Special Service Tool (SST) from the fuel feed tube and the delivery pipe.
(2) Connect the fuel feed tube and the delivery pipe.
Release Residual Pressure in Fuel Line
  
• There may be some residual pressure even after "Release Residual Pressure in Fuel Line" work, so cover the hose connection with a shop towel to prevent residual fuel from spilling out before disconnecting any fuel connection.
1. Turn the ignition switch OFF and disconnect the battery (-) cable.
2. Remove the fuel pump fuse (A).
3. Connect the battery (-) cable.
4. Start the engine and let idle, and then turn the ignition switch OFF after the engine has stopped on its own.

Fuel Tank Repair procedures

Removal
1. Release the residual pressure in fuel line.

(Refer to Fuel Delivery System - "Release Residual Pressure in Fuel Line")
2. Remove the rear seat cushion.

(Refer to Body - "Rear Seat Assembly")
3. Remove the fuel pump service cover (A).
4. Disconnect the fuel pump connector (A) and the fuel tank pressure sensor connector (B).
5. Disconnect the fuel feed tube quick-connector (C).
6. Disconnect the vapor tube quick-connector (D).
7. Remove the rear - LH wheel & tire.
8. Lift the vehicle and support the fuel tank with a jack.
9. Disconnect the fuel filler hose (A).
10. Disconnect the ventilation hose (B).
11. Remove the under cover (A).
12. Remove the brake line (A) bracket mounting bolts.
13. Remove the fuel tank from the vehicle after removing the fuel tank band (A).

  
• When removing the fuel tank, the fuel tank must be tilted because of interfering with coupling.
Installation
1. Installation is reverse of removal.
Fuel tank band installation nut :

39.2 ~ 54.0 N.m (4.0 ~ 5.5 kgf.m, 28.9 ~ 39.8 lb-ft)

Fuel Pump Repair procedures

Removal
1. Release the residual pressure in fuel line.

(Refer to Fuel Delivery System - "Release Residual Pressure in Fuel Line")
2. Remove the rear seat.

(Refer to Body - "Rear Seat Assembly")
3. Remove the fuel pump service cover (A).
4. Disconnect the fuel pump connector (A) and the fuel tank pressure sensor connector (B).
5. Disconnect the fuel feed tube quick connector (C) and the vapor tube quick-connector (D).
6. Remove the fuel pump after removing the locking ring (E) with SST[SST.: 09310-F3100] from the fuel tank.
7. Remove the fuel pump from the fuel tank.
Installation
1. Installation is reverse of removal.
  
• Be careful of fuel pump direction when installing (Refer to the groove in the fuel tank).
Fuel Pump Plate Cover Installation :

58.8 ~ 68.6 N.m (6.0 ~ 7.0 kgf.m, 43.3 ~ 50.6 lb-ft)

Fuel Filter Repair procedures

Removal
1. Remove the fuel pump.

(Refer to Fuel Delivery System - "Fuel Pump")
2. Disconnect the electric pump wiring connector (A) and the fuel sender connector (B).
3. Remove the head assembly (A) after releasing the cushion fixing hooks.
4. Disconnect the fuel tube quick-connectors (B).
5. Remove the fuel sender (A) in the direction of an arrow.
6. Remove the reservior-cup (B) after releasing the fixing hooks (A).
7. Disconnect the ground (A).
8. Release the fixing hooks, and then remove the pre-filter (A) and the fuel pressure regulator (B).
9. Remove the fuel pump motor (A) in the direvtion ofan arrow.

  
• Be careful of O-ring.
Installation
1. Installation is reverse of removal.

Fuel Pump Motor Repair procedures

Removal
1. Remove the fuel pump.

(Refer to Fuel Delivery System - "Fuel Pump")
2. Disconnect the electric pump wiring connector (A) and the fuel sender connector (B).
3. Remove the head assembly (A) after releasing the cushion fixing hooks.
4. Disconnect the fuel tube quick-connectors (B).
5. Remove the fuel sender (A) in the direction of an arrow.
6. Remove the reservior-cup (B) after releasing the fixing hooks (A).
7. Disconnect the ground (A).
8. Release the fixing hooks, and then remove the pre-filter (A) and the fuel pressure regulator (B).
9. Remove the fuel pump motor (A) in the direvtion of an arrow.
Installation
1. Installation is reverse of removal.

Fuel Sensor Repair procedures

Removal
1. Remove the fuel pump.

(Refer to Fuel Delivery System - "Fuel Pump")
2. Disconnect the fuel sender connector (A).
3. Remove the fuel sender (A) in the direction of an arrow.
Installation
1. Installation is reverse of removal.

Fuel Pressure Regulator Repair procedures

Removal
1. Remove the fuel pump.

(Refer to Fuel Delivery System - "Fuel Pump")
2. Disconnect the electric pump wiring connector (A) and the fuel sender connector (B).
3. Remove the head assembly (A) after releasing the cushion fixing hooks.
4. Disconnect the fuel tube quick-connectors (B).
5. Remove the fuel sender (A) in the direction of an arrow.
6. Remove the reservior-cup (B) after releasing the fixing hooks (A).
7. Release the fixing hooks, and then remove the fuel pressure regulator (A).
Installation
1. Installation is reverse of removal.

Fuel Line Repair procedures

Removal
1. Turn the ignition switch OFF, and then remove battery (-) cable.
2. Release the residual pressure in fuel line.

(Refer to Fuel Delivery System - "Release Residual Pressure in Fuel Line")
3. Disconnect the fuel feed quick-connector (A).
4. Disconnect the vapor hose (A) which is connected from the PCSV.
5. Lift the vehicle.
6. Remove the fuel tank.

(Refer to Fuel Delivery System - "Fuel Tank")
7. Disconnect the vapor tube quick-connector (A).
8. Remove the vapor tube line fixing clip (A).
9. Remove the fuel feed line fixing clip (A).
10. Disconnect the fuel & brake line protect (A) from the fixing clip.
11. Remove the fuel line fixing clip (A).
12. Remove the fuel line (A).
Installation
1. Installation is reverse of removal.

Filler-Neck Assembly Repair procedures

Removal
1. Remove the rear-LH wheel, tire, and the inner wheel house.
2. Disconnect the fuel filter hose (A) and the ventilation hose (B).
3. Open the fuel filler door and unfasten the filler-neck assembly mounting screw (A).
4. Remove the filler-neck assembly from the vehicle after removing the bracket mounting bolts (A).

Installation
1. Installation is reverse of removal.
Filler-neck assembly bracket installation bolt :

7.8 ~ 11.8 N.m (0.8 ~ 1.2 kgf.m, 5.8 ~ 8.7 lb-ft)

Accelerator Pedal Repair procedures

Removal
1. Turn the ignition switch OFF and disconnect the negative (-) battery cable.
2. Disconnect the accelerator position sensor connector (A).
3. Remove the installation nuts (A) and then remove the accelerator pedal module.

Installation
1. Installation is reverse of removal.
Accelerator pedal module installation nut :

12.8 ~ 15.7 N.m (1.3 ~ 1.6 kgf.m, 9.4 ~ 11.6 lb-ft)

Delivery Pipe Repair procedures

Removal
1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Release the residual pressure in fuel line.

(Refer to Fuel Delivery System - "Release Residual Pressure in Fuel Line")

  
• When removing the fuel pump relay, a Diagnostic Trouble Code (DTC) may occur. Delete the code with the GDS after completion of "Release Residual Pressure in Fuel Line" work.
3. Disconnect the injector connector (A).
4. Disconnect the fuel feed tube quick-connector (B).
5. Remove the installation bolt (C), and then remove the delivery pipe & injector assembly from the engine.
Installation
1. Installation is reverse of removal.
Delivery pipe installation bolt :

18.6 ~ 23.5 N.m (1.9 ~ 2.4 kgf.m, 13.7 ~ 17.4 lb-ft)
Engine Control System
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