Measure the fuel pressure at idle after installing a fuel pressure gauge to delivery pipe.
☞ Install a fuel pressure gauge after combustion in the fuel line by removing fuel pump relay.
■ Specification : 4.3~4.7㎏⁄㎠
Is the measured fuel pressure value within the specification?
 | ▶ Go to "Fuel remain pressure inspection" procedure as below. |
 | ▶ Repair or replace fuel filter and fuel hose. (whether it is blocked or not) ▶ If fuel pressure is too low, → Check/repair fuel filter blocked, fuel line folded/blocked. → Check/repair fuel pump(fuel pressure regulator) and fuel line leakage. ▶ If fuel pressure is too high, → Check/repair fuel pressure regulator stuck. |
Monitor fuel pressure at fuel pressure inspection as above.
Engine "STOP".
Check decrease in fuel pressure.
■ Specification : After engine stops, the gage reading should hold for about 5 minutes.
Does the fuel pressure remain after engine stop?
| ▶ Go to "High pressure fuel system" inspection procedure. |
| ▶ If fuel pressure drops slowly, check/repair injector leakage/fuel leakage in the fuel filter and fuel line. ▶ If fuel pressure drops immediately, check/repair fuel pump check valve stuck open/leakage. |
