Here is the run down i have to commute for 50 miles 1 way for school 2 times a week and this is all at 75-85 mph over 2k+ elevation difference from a to b.

i have replaced the plugs with al 103s gapped at 50
I have a new lq4 maf not a reman
new tps in the N* TB
new vac lines.
oil change
new fuel pump racetronix
sprayed ether looking for vac leaks but cant find any

the only things i have not changed or looked at is the
PCV
Fuel filter
IAC

When i drive in town the car will idle fine as long as i don't go over 50% throttle but if I hop on the interstate at anything over 2 miles when i stop at a stoplight the car hunt for idle and if i don't feather the gas it will stall out. The big thing is it will fire right back up after it stalls and then it will idle pretty ok not great but wont stall. Here is where it gets weird I did a scan with the WB hooked up and right before it stalls the afr will go from about 14.5:1 to 10:1, so I understand that this is basically meaning that the car is flooding and stalling out.

The only other weird thing is that the car keeps throwing a theft deterrent fuel enable signal not received (codep1626) and it had never done that before till I did the FP.

I have
42.5 injectors
PRJ rails
gen v and 1.9 in intense IC 3.0 mps
egr,evap and cat delete
coolant bypass
1.8 rr with l76 springs
ported LIM and new lim gaskets
180 stat
N* tb and lq4 maf with cone intake.
bonne tensioner and l26 alum motor mount
paces*****r headers
plx WB
HPT
hogan Cat back
stock replacement wires

I can post a scan and a copy of my tune if that will help.
i am just getting sick of fighting it and I want my car back that was not so much of a headache.
there is another cruising issue but i think that is cat test related from what i can glean from the reading have done.

Have you been using a different key at all? Maybe a valet key?

And what vehicle is this? The Regal?

My guess is the fuel pump. I understand the afr is going rich just before it stalls out, but that could be the ECU adjusting fuel trims to compensate for low fuel pressure. Scan your short term fuel trims and I'l bet that is what is happening.

I recommend you check the FPR (smell for gasoline in the vac line) and if that is okay get the fuel pressures checked.