91 Plymouth Sundance 2.2 engine. I replaced the fuel pump, fuel pressure regulator and the Automatic shutdown relay that also acts as fuel pump relay...no power getting to fuel pump...any ideas?

The engine computer must see oil pressure or engine RPM to turn the pump relay on. Otherwise you only get power from the relay when the key switch is first turned on.
You could try to bypass the pump relay to see if the engine will run.

If you feel like the engine is still ok, I would look at the oil pressure and check engine light issues.
On engines with fuel injection, the fuel pump is powered by the pump relay until the engine starts. Then the engine has to have oil pressure to keep the fuel pump powered.
Its a safety feature so if you are in a wreck the fuel pump does not keep running if the engine is off.
I would want to know why the oil pressure light is staying on and what the trouble codes are in the computer.

disconnect power supply to fuel pump, then start engine when engine stalls fuel pressure released

I suggest the following:

Perform a OBD-I diagnostic scan;
Check and replace the fuel filter;
Test the fuel pressure with a fuel pressure gauge;
Check the fuel pressure regulator; and,
Check the fuel pump fuse and relay.

The diagnostic scan will immediately identify your problem. This is imperative should the fuel pump be inoperative.

Hi.

Check the fuel filter and fuel pressure regulator. They are part of the same assembly and are located on top of the fuel pump. To replace the regulator # Disconnect fuel supply line at the Filter/Regulator nipple and releas locking spring tab (2 in diag.) on the regulator, then turn counterclockwise and pull out. To test regulator use a gauge like this in fuel lines:Pump Pressure Tester.
Pressure in 2003 should be 58psi (48 in 2001 engines). Pressure will drop of about ten psi when you start engine.

There is also an automatic shut down relay ASR. If problem is the ASR the pressure will go down when the relay cuts off power to pump. Read voltages and see if the problem is electrical first before going for the regulator.

When you turn the ignition on the pump is energized for 2 to 3 seconds. did you check it like that. it is also energized when cranking the engine. there is a fuse then a relay then the fuel pump. the relay is ran/ energized by the ecm computer. if there is a fuse relay box under the hood you'll need to check there to. good luck

CHECK FUEL PUMP FUSE LOCATED BEHIND THE STEERING COLUMN ABOVE THE HOOD LATCH LEVER.IF FUSE GOOD REPLACE THE AUTO SHUTDOWN RELAY LOCATED ON INNER FENDER PANEL NEAR THE BATTERY.IF ALL IS GOOD SCAN CAR FOR ECM FAULT CODES.

check the fuel pressure regulator and the oil level.

There is not an fuel pump reset button. There is however an Automatic Shutdown Relay that acts as a fuel pump shutdown. On the 1998 Model: It should be located in the Junction Box located under the leftside of the dashboard There should be a cover over the top of the Junction Box. On the backside of that cover is the identification and location of the Relays and Fuses. If there is no cover, your Owner's Manual should have a schematic identifying the location, position, and type of Relay and Fuses. There should be additional Fuses involving the Fuel Pump. Make sure you not only check the Relay and Fuses to see if they are good, also check with a Voltmeter to check for voltage, with the Key in the "ON" (not start) Position; it should read approximately 12v,

With approx 12v present at the Relay and Fuses, one quick way to determine if there is Voltage to the Fuel Pump:
1) With a Partner behind the wheel. Take the Gas Cap off and place your ear up close to the opening of the Gas Filler Tube. Have your Partner turn the Key to the "ON" (not Start) Position. You should be listening for a humming sound (for 2-3 seconds)meaning the Fuel Pump is getting power (volts).
2) If there is no "humming" or you are not sure, get underneath the Van next to the Gas Tank and have your Partner do it again. Listen for a humming.
3) If there is definitely no humming present with good fuses, relays and voltage, then most likely the Fuel Pump is bad.
4) However, a lot of Fuel Pumps have been replaced only to find out the Pump was good, but the electrical wiring harness was bad and the real culprit.
5) You will have to slightly lower the Fuel Tank to gain access to this electrical connection.
6) After you disconnect the electrical connection, using the Voltmeter check for approximately 12v coming from the Wiring Harness/Connector.
7) Inspect the Wiring Harness/Cnnections for any signs of burns, melting, or shorting. Repair this wiring harness before deciding to replace the fuel pump needlessly.
8) After repairing the Wiring Harness/Connection: Replug it back in and recheck the Fuel Pump one last time.
9) If still no "humming" the Fuel Pump needs to be replaced.

If there is humming from the Fuel Pump, then there are four possible problems.
a) Fuel Filter (when was the last time it was replaced?) It could be clogged, prohobiting fuel flow.
b) Fuel Regulator. Located on the Fuel Rail where the Fuel Injectors are. If there is a presence of Gas in the Vacuum line (the only rubber line on the Fuel Regulator) attached to the Regulator, then the Diaphram of the Fuel Regulator is broke and Gas is not reaching the Fuel Injectors. Instead it is being dumped into the Intake. Replace the Regulator.
c) Fuel Injector Circuitry problem. Using an Auto Stethoscope: Place the Stethoscope end in each individual Fuel Injector. Have your Partner attempt to start the Van. If there is no evident and rythmic "clicking" (fuel injector's gate opening and closing) then the Fuel Injector is faulty or the electrical connection is faulty. To check to find out which is faulty, switch Fuel Injectors (one clicking with one not clicking) and recheck for the clicking.
d) Clogged Fuel Injectors. With the Fuel Rail (with the Fuel Injectors) removed out of the engine. Place clear Plastic tubing over the nozzle ends of all exposed Injectors. With a Partner Starting the Engine, look for
(1) Fuel Flow (presence).
(2) Fuel Spray (pressure).

Let me know if this helped, or if you have any additional information or questions. Feel free to contact me at FixYa.com!

i need to know is it a 4 or 6 cilinder??