97 ram 1500

So I have what feels like a sputter/slight jerking so to say when cruising along and letting off gas a bit and re applying.

first changed u joints on rear drive shaft as it felt rotational. NO CHANGE
also changed TPS, IAC- NO CHNAGE

so I did a fuel pressure check (no shrader valve)
did In line and didn’t start the truck- turned key to accessory… as that’s what I thought the procedure was and had about 42 . Just below spec.

then I seen you should start and should be at 49.
Should I re do test?
Use this test and say it’s good? Or bad?

I have map and fuel injector seals and screens going in next l.

 

I would check it engine running. See what it says.

 

Accessory shouldn't turn on the pump, Ignition on (first click) will charge the system. It should go up to 49psi. If it's low start the engine and see if goes up any more. Either way the pump is not building full pressure at key/ignition on and should be replaced.

 

I went to key on. Bad verbiage on my part.
I just read it should be 45 with ignition on with truck not started was 42. Looks like I should re do the test and start the truck. The fuel pump is working just have a little sputter and trying to figure out if it is on the brink of going out