Hyundai Sonata 1991 Shop Manual page 259

Fuel Pressure Test
MPI SYSTEM
Y31DROA
1. Reduce the internal pressure of the fuel pipes and hoses by
the following procedures.
o Disconnect the fuel pump harness connector at the fuel
tank rear side.
o Start the engine and after it stops by itself, turn the igni-
tion switch to OFF.
o Disconnect the battery negative (-) terminal.
o Connect the fuel pump harness connector.
2. Disconnect the high pressure fuel hose at the delivery side.
CAUTION
Cover the hose connection with rags to prevent splashing
of fuel that could be caused by residual pressure in the
fuel pipe line.
3.
Using the fuel pressure gauge adaptor,
(09353-24000,
09353-24100, 09353-24200)
install the fuel-pressure
gauge to the delivery pipe. Tighten the bolt to the specified
torque.
Tightening torque
Fuel pressure gauge to delivery pipe .
25-34 Nm (250-350 kg.cm, 18-25 Ib.lt)
4. Connect the battery's negative (-) terminal.
5. Apply battery voltage to the terminal for the fuel pump drive
and activate the fuel pump; then, with fuel pressure applied,
check that there is no fuel leakage from the pressure gauge
or connection part.
6. Disconnect the vacuum hose from the pressure regulator,
and plug the hose end. Measure the fuel pressure at idle.
Standard value .
320-340 kPa (3.26-3.47 kg/em', 46-49 psi)
31-34
"-.
31Y268