'03 6 ltr erratic idle after fuel pump change

[wetneck]

Truck died on me yesterday, then battery died after trying a dozen or 2 times trying to start.
Replaced Batt, still no start.
Checked rail pressure , was at 30 lbs.
Dropped tank, fun, installed new fuel pump, 50 lbs steady, should it be 55-65 ?
started fine but now has a stumbling idle.
Everything seemed to go back together right except the larger line on pump, the fitting inner stayed on old pump...slid it off and put it on new nipple. IF this was the issue wouldn't it be leaking there ?
Any suggestions on What to check/do now ??
Thanks

 

oh this IS in an 03 escalade ext, wasn't getting any answers on the caddie forum so I thought I'd try here.

[sefiroxx]

Change fuel filter as failing pump may have junked up filter.

Check codes.

Check fuel pressure regulator for leaks, may want to replace anyway

Hook scanner up and check short term fuel trim to see if lean or rich.

[Supreme Pizza]

9 minutes ago, sefiroxx said:

Change fuel filter as failing pump may have junked up filter.

Check codes.

 

[wetneck]

The filter is included on the fuel pump ?

Yes I guess I'll need to take it somewhere as I don't have a tech2, do have an odb2 but don't think that'll work

[sefiroxx]

There is a small filter in the pump and a larger one on the fuel line around the driver side.

Better obd2 scanners have the ability to pull some of the real time data streams like temp, RPM, fuel trim (o2 sensor data) etc

[wetneck]

Thanks, I wasn't aware of the second one, that'll be next.

Then off for a code scan.

[txab]

Take pressure reading key on, engine off.

 

Replace rail fuel filter and check FPR on the engine as noted above

[wetneck]

FP is right at 50, key on-eng off , eng running and engine revved.

Seemed to clear up  a bit last night but today will retest.

Is it supposed to be 55-65 ??

 

[no HD]

The stumbling idle issue could be the computer taking it's time relearning everything. With battery replacement sometimes it takes longer than you would think.

[wetneck]

I wondered about this as I don't have a service manual, or if I needed to do a "reset" after fp install.it seems these components like to be de-energized,  whether it be by battery, fuse, etc.

Had to do something similar to reset the blend door, prior I would just replace.

[txab]

Again check the fuel pressure regulator under hood. It may be faulty and causing the low pressure

[wetneck]

Checked the reg, pressure changed and no fuel at either end

[sefiroxx]

Does the fuel pressure change under different RPM‘s? If not, then regulator or guage is stuck