help cant get rb25 to run properly

[forum26]

so i have a 91 gtst that i put a s2 rb25 in this winter. i just got it all hooked up and it starts up great and runs for 5-10sec then rpms drop lower and lower and it shakes until it dies. giving it pedal only speeds this up. I vacuum tested thinking it was a major vaccum leak and when it did this the vacuum test read -18 ish then dropped quickly until dead. Cant find any vacuum leaks though. I disconected the MAF and it runs and doesnt die. Vacuum staying at a solid -17 to -18. So if vacuum is fine while its running with no MAF that means i have no vacuum leaks correct? And then would it point to a bad MAF? Im not sure if i got a S1 or S2 MAF but i dont know if it would make a difference if i do have the wrong one? Any help appreciated thanks.

[Cjmartz2k]

Bad MAF. Also, the MAF needs to match the ecu you are running.

[forum26]

ive looked alot on the internet and the maf i have has a pink label e60 i beleive which i have read is the s2 MAF? i have a s2 engine an ecu

[Cjmartz2k]

Sounds correct off the top of my head. Try a different pink label e60 MAF. Also, check the MAF wiring for shorts.

[forum26]

hmm so theres 3 wires going into the plug 1 black 1 white an 1 black/white. the voltage from the black/white one to the black one is like 12v ish mabye a little more and then the white to the black is 8ish but im read that the pin the black wire goes to is the signal wire? but the only way i can check voltages is if i use the black one as a ground. any thoughts?