Hyundai Tucson: Fuel Delivery System / 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 relay, the Diagnostic Trouble Code (DTC) will be occurred. Therefore delete the code with the diagnostic tool after "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 : 480 - 520 kPa (4.9 - 5.3 kgf/cm, 69.6 - 75.4 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 open stuck | 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 relay, the Diagnostic Trouble Code (DTC) will be occurred. Therefore delete the code with the diagnostic tool after "Release Residual Pressure in Fuel Line" work.
6.Test End
(1)Remove the Special Service Tool (SST) from the fuel feed tube ant the delivery pipe.
(2)Connect the fuel feed tube and the delivery pipe.
Components and Components Location
- Component Location
[Fuel Tank]
1. Fuel tank2. Canister3. Vapor hose4. Canister Close Valve (CCV)5. Vent hose6. Fuel filler hose7. Fuel tank air filter8. Fuel Tank Pressure Sensor (FTPS)9. Fue ...
Release Residual Pressure in Fuel Line
- 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 ...
Other information:
Hyundai Tucson (NX4) 2022-2025 Service Manual: General Safety Information and Caution
- Precautions
General Precautions
Please read the following precautions carefully before performing the
airbag system service. Observe the instructions described in this
manual, or the airbags could accidentally deploy and cause damage or
injuries. • Except when performing electrical ins ...
Hyundai Tucson (NX4) 2022-2025 Owner's Manual: Child Restraint System (CRS)
Children Always in the Rear
WARNING
Always properly restrain children in the
rear seats of the vehicle. Children of all
ages are safer when restrained in the rear
seat. A child riding in the front passenger
seat can be forcefully struck by an
inflating airbag resulting in serious injury ...
