Fuel system issue

[Muttjr12]

I have a 99 jeep wrangler tj, I've replaced my fuel pump last summer, did a full tune up, had a shop replace my crank shaft sensor and my issues stopped. Now my issues are back and I replaced the relay and fuses.

Still having issues with my jeeps fuel cutting out and occasionally my fuel pump does not engage when the key is turned to the on position.

What would cause my fuel pump to cut out again?

 

[Jerry Bransford]

If your fuel pump sometimes doesn't run when first turning the key on, it could be a bad fuel pump, a bad connection like at the power plug on the gas tank support, or perhaps a problem inside the power distribution center like at its ASD (auto shutdown) relay which is what powers the fuel pump.

 

[Muttjr12]

My fuel pump also shuts off while driving and lags the engine, occasionally shuting the engine off causing me to pull off the road and restarting it. While restarting, I sometimes have to pop the hood and play with my relays and fuses to get the fuel pump to engage.

I replaced my ASD relay at the same time I replaced my fuel pump relay. And after replacing my fuel pump last summer and had my crank shaft sensor replaced all my issues went away until recently.

 

[Jerry Bransford]

My fuel pump also shuts off while driving and lags the engine, occasionally shuting the engine off causing me to pull off the road and restarting it. While restarting, I sometimes have to pop the hood and play with my relays and fuses to get the fuel pump to engage.

I replaced my ASD relay at the same time I replaced my fuel pump relay. And after replacing my fuel pump last summer and had my crank shaft sensor replaced all my issues went away until recently.

I'd certainly inspect the fuel pump's wiring from the connector on the fuel pump to its connector on the gas tank support to the ASD relay. Look under the PSD too, you only need to remove a couple small sheet metal screws to lift it up.

 

[ATLparanormalOG]

I'd certainly inspect the fuel pump's wiring from the connector on the fuel pump to its connector on the gas tank support to the ASD relay. Look under the PSD too, you only need to remove a couple small sheet metal screws to lift it up.

Jerry...I did a fuel pressure test on my 2.5 today. Read zero with the key turned on. Several times cycling the key did not do anything. Starting the engine and it took several tries...more than normal but that was due to my having to disconnect the fuel rail and put an adapter on since I don't have a Schrader. Usually between 1-4 tries to start. Anyway, it starts to build pressure when the starter is engaged. She starts, but never gets above 25 psi. Also when the vehicle is shut off, pressure almost immediately drops back to zero. Does that sound like a check valve in the regulator, or the fuel pump, or and electrical issue?

 

[Jerry Bransford]

With the fuel pressure dropping off nearly immediately I'd guess it's the check valve inside the fuel pressure regulator which sits outside the gas tank on top of the fuel pump assembly.

This thing I'm holding that will replace the old one still installed below it.

 

[ATLparanormalOG]

With the fuel pressure dropping off nearly immediately I'd guess it's the check valve inside the fuel pressure regulator which sits outside the gas tank on top of the fuel pump assembly.

This thing I'm holding that will replace the old one still installed below it.

View attachment 318807

Yeah...I'm aware of it's location. I figured that as well. The fact that it won't get above 25 psi is what makes me hesitate though. Of course, if one thing is wrong in the regulator, more could be clabbered. I'm surprised that it runs decently with only 25 psi. Having a little trouble locating just the regulator. Seems that most places are listing the little secondary one on the fuel rail.
Thanks!