Will not stay running

Good evening,

The fuel pressure is good. You are right on the button.

What I would try is a security reset to see of the key forgot the password for the system.

https://www.2carpros.com/articles/how-to-reset-a-security-system

Roy

CONDITIONS

IMPORTANT: If a new vehicle control module (VCM) is being installed for the first the manufacturing enable bit will be set and the auto learn procedure may not be necessary.

The following procedure allows for anyone to reprogram the PASSLOCK/EVO module learned data code with any tools, other than the scan tool, when any of the following parts are replaced:
The PASSLOCK TM/EVO module
The PASSLOCK sensor
The VCM

The PASSLOCK/EVO module will set the DTC B3031 module in the learn mode when entering the reprogramming procedure.

STEPS

IMPORTANT: Erase the PASSLOCK related diagnostic trouble codes (DTCs) that are stored in the VCM. If there are any powertrain related DTCs, record these DTCs and refer to A Powertrain On Board Diagnostic (OBD) System Check in Computers and Control Systems - 4.3L

In addition to the time involved in performing the specific steps, the Seed and Key procedure accomplishes the same task in 10 minutes as the Auto Learn procedure does in 30 minutes. To perform the Seed and Key Learn procedure, refer to PASSLOCK Reprogramming Seed and Key. See: Antitheft and Alarm Systems > Procedures > PASSLOCK Reprogramming Seed and Key

The following is the Auto Learn Procedure:
1. Insure the ignition key is in the ON position.
2. Clear all PASSLOCK/EVO module and VCM DTCs. Record and refer any VCM DTCs to A Powertrain On Board Diagnostic (OBD) System Check in Computers and Control Systems - 4.3L
3. Momentarily rotate the ignition key to the CRANK position (Do NOT start the vehicle), then release it to the RUN position (Do NOT key OFF in the process).
4. Wait 10 minutes. Observe the SECURITY indicator. Refer to the following list for the appropriate responses:
If the PASSLOCK sensor was replaced the SECURITY indicator will flash for the 10 minutes duration.
If the PASSLOCK/EVO module was replaced, the SECURITY indicator will flash for a few seconds and then remain ON for the remainder of the 10 minutes duration.
If the VCM was replaced with a new programmed VCM and connected to the vehicle for the first time, the vehicle will Stand and this procedure may not be necessary.
If the replacement VCM was connected to any vehicle at any other time, even momentarily, the SECURITY indicator will flash for a few seconds and then remain ON for the 10 minutes duration.
5. The SECURITY indicator will transition from flashing to ON briefly to OFF after 10 minutes if remaining in the ignition ON position.
6. Turn the ignition switch to the OFF position and wait for 10 seconds.
7. Repeat steps 3-6 two more times. The new security code is ready to be communicated among the PASSLOCK sensor, PASSLOCK/EVO module and VCM. The new password is learned on the next ignition lock cylinder cycle from OFF to CRANK to ON (start attempt).

You could call a locksmith to come to your house and replace the keys and program them right there.

Much cheaper than the dealer process.

Roy

In the key, yes, there is no chip but it is still part of the security system itself.

Roy

Okay, let us back up.

Can you check for any codes in the system?

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Does the security light or theft light come on when toy turn the key on? If it does, does it go out after about 10 seconds?

Roy

The design of the Passlock(TM) system is to prevent vehicle theft by disabling the engine unless the Passlock(TM) lock cylinder rotates properly by engaging the correct ignition key. The system is similar in concept to the passkey system. However, the Passlock(TM) eliminates the need for a key mounted resistor pellet. The components of the system are as follows:
The ignition lock cylinder
The ignition switch
The Passlock(TM) sensor
The Passlock(TM)/EVO module
The security indicator
The Vehicle Control Module (VCM)