Non Trouble Code Components

Fuel Pressure Solenoid Circuit:

To test the Fuel Pressure Regulator Solenoid Valve, located on the left side of the firewall, proceed as follows.


COMPONENT TEST
1. Disconnect the black vacuum hose from the inlet port of the solenoid and connect a vacuum gauge to the fitting.
2. Start the engine and confirm that vacuum increases as engine speed increases. (if it doesn't, the vacuum hose may be split between the solenoid and the intake chamber).
3. Connect a hand vacuum pump to the fitting that the hose was disconnected from.
4. Disconnect the electrical connector.
5. Apply battery Voltage to the electrical connectors as shown.

EGR Voltage Test:

6. Apply vacuum to the solenoid with the pump and note the results.
a. Vacuum should hold when Voltage is applied.
b. Vacuum should NOT hold when NO Voltage is applied.
c. Vacuum should hold when Voltage is applied and remaining nipple is covered by finger.

EGR Resistance Test:

7. Using an ohm meter check the resistance across the solenoid terminals.

Resistance:
36 - 44 Ohms @ 68° F.


HARNESS TEST
1. Disconnect the fuel pressure regulator solenoid connector and turn the key to the ON position.
2. Using a Voltmeter, measure the power supply Voltage between the harness connector terminal 1 and ground.

Voltage:
System Voltage.

3. Turn the key OFF and disconnect the negative battery cable.
4. Using an Ohmmeter, check for continuity between the ECU harness connector terminal 57 and and solenoid connector 2.

Continuity:
Should exist.

5. Disconnect the ECU connector. Using an Ohmmeter, check for continuity between the ECU harness connector terminal 57 and ground.

Continuity:
Should not exist.

6. Using an Ohmmeter, check for continuity between the solenoid connector terminal 2 and ground.

Continuity:
Should not exist.



If any of the previous tests produce unsatisfactory results, the harness will need to be repaired or replaced. Once repairs have been completed, clear the trouble codes and road test the vehicle to confirm that the repair has corrected the problem and the code doesn't return.
If the trouble code returns, it is possible that there is an intermittent failure of the component or the ECU. Check for looseness at all harness junctions and test for an intermittent failure.