It will start and run, I drive it down the road and it starts cuting in and out like its running out of gas ! I mash it to the floor and it straightens out for a few minutes. I replaced the fuel pump and the fuel filter , what could be wrong now ? Thanks for any info

 

Forgot to mention it is a 4 door 4x4

 

Do the spark plug wires connect to the distributor cap horizontal or vertical? (2 different systems in 95, 2 different diagnosis procedures)
Fuel pressure and leakdown need to be checked. Most auto parts stores rent/loan/sell fuel pressure testers: When you have one at your disposal, let us know and we can explain how to test the fuel delivery system, (just because the pump is new, doesn't mean it's good).
Is the check engine light on, or does it flash while driving?

 

The plug wires are horizontal,I will get a fuel pressure tester. Thank you very much for your help

 

Your engine is equipped with CMFI, (central multiport fuel injection). It has one fuel injector, it has EDI ignition system, a crankshaft position sensor, and is controlled by OBD1.5 engine controls. Kind of a "OBDII wanna be" system, but it works

Connect the fuel pressure tester to the service port next to the distributor, driver side. When you initially turn the ignition to the RUN position, (don't start the engine) the fuel pump will be activated for ~2 seconds and then deactivate. Fuel pressure must be tested while the pump is activated. Pressure must be 55psi to 61psi and it must remain above 50psi for at least 10 minutes after the pump deactivates. Check it several times and watch for consistent numbers. If it fails one or both parts of the test, there is a problem with the fuel delivery system. It does not tell what the problem is, only that a problem exists. To pinpoint the problem, more tests are necessary. Post your readings.

 

The wires are horizontal, I was wrong

 

OK, corrections were made in post #5.

 

How is your oil pressure? As fuel pump runs off of oil pressure could be weak op sending voltage to fp relay.
Hook wtf is OBD 1.5?

 

It has very good Oil pressure

 

LOL, OBD1.5 is a transition between OBDI and OBDII. Early production 95's have OBDI, late production 95's have OBD1.5. It is not fully OBDII compliant, but it is better than OBDI. The OBD1.5 system is one of the reasons Oldsmobile did not produce the Bravada in 1995. Apparently they thought it wasn't "good enough" and didn't want a "mid year switch" in systems.

FYI: GM hasn't used the oil pressure sending unit, (OPSU) to exclusively supply voltage to the fuel pump since the mid 80's. There is a circuit on 95 4.3L that goes through the OPSU. It accomplishes two things: 1) is to supply the fuel pump with an additional path to enable more amperage flow to the pump when oil pressure is above ~7psi. If oil pressure drops below that, the pump is still powered by the fuel pump relay. The second reason is to keep the fuel pump activated for a couple of seconds after the ignition is turned off. This allows the pump to pressurize the system for the next start up. On 96 and newer, they just programmed the PCM to leave the pump activated for ~2 seconds after shut down, and did away with the OPSU circuit.

On 1995 and older 4.3's, when the engine is running, if you disconnect the oil sender, the pump will continue to run. On the other side of the coin, if the oil sender contacts stick on shut down, the fuel pump will run continuously after you shut the engine down. I'd have to check the schematic to see which circuits OBD1.5 has.... never looked my guess is that it does not have the oil pressure sender circuits.