3k RPM rev-cut and multiple codes, please help!!

[FAILasaurusRex]

Hi guys, Im new to this forum thank you for your time. A little background info on my car before I get into my problems - I have a S13 coupe drift car with a first gen 1uz in it, manual trans conversion to nissan trans with light flywheel and 6 puck clutch. Engine is out of a 91 LS400, new timing set with water pump and full tune up (plugs, wires, caps, rotors); ECU, harness, MAFS and Coils are from 93 SC400. The car itself is full racecar status wiring wise, it has a custom chassis harness and starting/charging system both built by myself, so I do not use any factory lower harness and my instruments are all aftermarket. I have been dealing with a lot of issues with my swap so far and getting frustrated with it.

Currently it wont rev above 3000 RPMs, two step limits like it is in limp mode or something, throwing codes 21, 27, 28, 29. I dont have downstream 02 sensors, and my upstreams are single wire instead of 4 wire. I am aware that is probably what is causing most of those codes, just curious if that could be causing the limiter? It idles great, runs butter smooth, just wont go above 3k.

Any help you guys can offer is much much appreciated, thank you for your time

P.S. I can post pictures and stuff later when im not on my work computer if ya wanna see anything

 

[gloverman]

What ECU number are you running?

 

[FAILasaurusRex]

I'm not sure, I'll try to find out today (my car is at my buddies house because I just moved) I'm also unsure if I need to do anything like ground out the neutral signal or something? Info on this sort of thing is so sparce

 

[gloverman]

With most toyota ECU's when the gearbox is not connected the ECU defaults to a drive gear so no need to do anything else in that department.

 

[FAILasaurusRex]

Ok, that is nice to know. I haven't been able to find out what number the computer is yet, I think I will just try to get a few o2 sensors and try to plug them in and see if that helps. I do have plans of going stand alone some time this next year so I'm not trying to spend much more money to get it to run proper on the stock computer ya know