Fuel Pressure Test: Notes

WARNING: This page is about a different car, the 1997 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: For additional information on fuel pressure and fuel pump testing procedures, see appropriate NO TROUBLE CODE (NTC) TEST and NO START (NS) TEST in Figure .

Power distribution center is located at driver's side front corner of engine compartment.
Start engine and allow to idle until engine stalls. Attempt to start engine several times. Once engine will not restart. Turn ignition off.
Disconnect electrical connector from any fuel injector. Connect jumper wire between one electrical terminal on fuel injector and positive battery terminal. Connect another jumper wire to remaining electrical terminal on fuel injector.
CAUTION: DO NOT apply battery voltage to fuel injector for more than 4 seconds or fuel injector may be damaged.
Momentarily touch remaining end of jumper wire to negative battery terminal for no more than 4 seconds. This energizes fuel injector and releases most of the fuel pressure. Fuel lines may now be disconnected. Cover fuel lines with shop before disconnecting, as some residual fuel pressure may exist.
Disconnect jumper wires. Reinstall electrical connector on fuel injector. Reinstall fuel pump relay. Diagnostic trouble codes may be stored in Powertrain Control Module (PCM) when fuel pump relay was removed. To clear diagnostic trouble codes from PCM, see TESTS W/CODES - 3.9L article.

CAUTION: When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See the COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION section before disconnecting battery.

NOTE: Some 3.9L models use fuel pressure test port mounted on fuel rail, near throttle position sensor, and some models do not. Note if fuel pressure test port is used, then refer to appropriate fuel pressure test procedure.