Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
System Inspection
- Check air leakage
- Visually/physically inspect the air leakage in intake/exhaust system for the following items:
Vacuum hoses for splits, kinks and improper connections.
Throttle body gasket
Gasket between intake manifold and cylinder head
Seals between intake manifold and fuel injectors
Exhaust system between HO2S and three way catalyst for air leakage
- Is a problem present?
YES
- Repair or replace as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
- Go to " 2 Check the fuel line" as follows
- Visually/physically inspect the air leakage in intake/exhaust system for the following items:
- Check the fuel line
- Check the fuel line for the following items:
Connector connection state
Damage/connection state for vacuum hoses connected to fuel line
Bent/pressed/twisted fuel line or fuel leakage
- Is a problem present?
YES
- Repair or replace as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
- Go to " 3 Check fuel pressure" as follows
- Check the fuel line for the following items:
- Check fuel pressureCAUTION:
- Be cautious that Fuel is explosive and an empty fuel tank can still contain explosive gases. When working on fuel system make sure to supply adequate ventilation to the work area. Do not smoke, and keep sparks and open flames away.
- The fuel system remains under pressure when the engine is not running. Release fuel system pressure before disconnecting any fuel line to reduce the chance of personal injury or fire damage to vehicle components.
- IG "OFF" and disconnect Fuel Pump Relay in Junction Box.
- Start the engine and wait for the engine to stall.
- IG "OFF" and connect Fuel Pump Relay.
- Install the fuel pressure gauge to the delivery pipe with the fuel pressure gauge adaptor.
- Activate the fuel pump, and with fuel pressure applied, check that there is no fuel leakage from the pressure gauge or connection part.
- Measure the fuel pressure at idle.
- Specifications : 374.6 ~ 384.4 kPa (3.82 ~ 3.92 kg/cm2 , 54.3 ~ 55.8 psi)
- Is the measured fuel pressure within specifications?
YES
- Go to "COMPONENT INSPECTION " procedure.
NO
- Repair or replace according to the table indicated below, and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
Possible Cause CHARTCondition Possible Cause Fuel Pressure is too low Fuel filter, fuel pressure regulator, in-tank fuel hose or the fuel pump Fuel Pressure is too high Fuel pressure regulator, hose or pipe
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.