Fuel Pressure (Rio)
- Release fuel pressure. See FUEL PRESSURE RELEASE . Disconnect high-pressure fuel hose from fuel delivery pipe. Cover hose connection using rags to avoid spraying of fuel. Disconnect battery negative cable. Install fuel pressure gauge (0K2A1 131 001A) on to high-pressure fuel line. See Fig 1. Connect battery negative cable.
- Using fuel pump check terminal connector, operate fuel pump and ensure no fuel leakage is present at pressure gauge or connection. See PRIMING FUEL SYSTEM . If no leaks are present, check fuel pressure. See FUEL PRESSURE SPECIFICATIONS table.
- If fuel pressure is greater than specified, check for sticking fuel pressure regulator or a restricted or bent fuel return hose or pipe. Repair or replace fuel hoses or pipes and fuel pressure regulator as necessary. See FUEL PRESSURE REGULATOR
under FUEL SYSTEM in REMOVAL, OVERHAUL & INSTALLATION article. If fuel pressure is less than specified, go to next step.
- Clamp return line and check if fuel pressure rises. If pressure does rise, replace fuel pressure regulator. See FUEL PRESSURE REGULATOR
under FUEL SYSTEM in REMOVAL OVERHAUL & INSTALLATION article. If pressure does not rise, measure fuel pump maximum pressure. See MAXIMUM FUEL PRESSURE (RIO & SPECTRA) .
- Stop engine and check for decrease in fuel pressure gauge. See HOLDING FUEL PRESSURE (RIO & SPECTRA) . Fuel pressure should hold for approximately 25 minutes. If fuel pressure decreases slowly after engine is stopped, check for leaking injector. See FUEL INJECTOR LEAKAGE TEST under FUEL INJECTORS. Replace fuel injectors as necessary. If fuel pressure decreases immediately after engine is stopped, check-valve inside fuel pump is not working. Replace fuel pump. To replace fuel pump, see FUEL PUMP
under FUEL SYSTEM in REMOVAL, OVERHAUL & INSTALLATION article. After repairs are completed, recheck fuel pressure.
- After testing is completed, release fuel pressure. See FUEL PRESSURE RELEASE . Disconnect fuel pressure gauge from adapter. Ensure hose connection is covered by shop towel to prevent fuel spray. Remove adapter bolts and adapter. Replace any old seals with NEW seals, and reinstall fuel line. Apply battery voltage to fuel pump drive connector terminal. See Figure. Check for fuel leaks. Repair any leaks as necessary.
Courtesy of KIA MOTORS AMERICA, INC.