SR won't idle HELP PLEASE!!!

[7o7drft240sx]

My car started to have idle problems out of no where and i can't seem to find what the problem is the past couple of days..i got a s13 redtop in a s13 chasis.....I've checked for codes and it pulled a code 12...switched the mafs with the ka-e mafs and nothing..it shows code 55 now which i think is normal rite?...it'll start up fine and everything, then when it starts to warm up it'll just go lean/hesitate and starts to die...PLEASE HELP ME!!! it's my dd.

Things I've checked...

switched Mafs
Switched fuel pump
sprayed carb cleaner in iacv

[frankies1390]

maybe check your TPS sounds like the throttle plate is shutting, ive had very similar problems and it was just a huge process of elimination. my problem was the o-rings were leaking when they were warm??? how to this day i do not know? but i would check to see what fuel pressure you're gtting and your tps. how is your battery voltage? check your alternator fuse i know it sounds dumb but my buddy's was blown and his car had the same symptoms.

[7o7drft240sx]

my fuel pressure is at 40..i know its suppose to be 36 but i just put it at 40 just because...battery volt is 12.6 and how do you check tps??

[nissans13240sx]

Any air leaks in between the maf and turbo?

[PyR0NiAk]

Diagnose it like any other car. Check the basics. Fuel, Spark, Timing, and Compression.

[7o7drft240sx]

Its been a while but I just wanted to let you guys know that I fixed the problem, all I did was got a new 02 sensor. I didn't replace that when I did the swap, stupid me. But thanks for all the help guys.

[PyR0NiAk]

Glad your issue was simple.