Fuel pump voltage

I am trying to trace down a problem with my 95 s10 blazer. It shutters/jerks while accelarating and at cruise speeds.

The other day while trying to diag the problem I ended up stranded at the gas station. Just filled it up and it wouldn't start. Turned over fine but no start.

I know how to listen and even test for fuel pump so I ran those test and wasn't getting any sound. So, I tow it home, pull the pump, take it to replace and the guy hooks it to a battery and it fires... So, he replaces it with a new one anyway and sends me on my way.

I tested the voltage at the relay in the glove box and I'm getting 11.4x or close. I have not tested with the relay in place as I'm not sure how, do I go under the dash, is there some connector there that will be obvious?

I did test at the three pronge connector at the tank and I'm only getting about half of that. Say 6.3 or such.

If I hook the overide to the battery (small red wire under hood for fuel pump testing) I get the full 11.4x at the three pronge connector.

The new pump fires everytime now and the vehicle starts. But as I said I am still getting the stuttering/jerking feel when cruising or accel.

Am I looking at this right. Shouldn't I get a full voltage load via the Relay to the three pronge connection as I did with the override wire?

Do I just randomly test the voltage along the wire harness, and how, since it's all wrapped and insulated and such.

Anyone know what the voltage reading at the connector on the gas tank should be?

Have you checked your fuel pressure at the shrader valve yet? Have you checked for a leaking fuel pressure regulator / nut kit? If not, pull your IMTV and have a look inside the intake for puddles of fuel / washing. It *should* be dirt black and carbony in there.