Okay I have no codes, But AS SOON as i hit about 4000RPM i go into LIMP MODE, i believe its not sending the proper voltage when i hit that rpm range, ANY ideas please???????????????

 

If you aren't getting any codes, how do you know for sure it's limp mode?

What mods are on the car? When did it start happening? What's your boost level when it happens?

 

Well, it wont go over 40mph, it runs great until than, and ive had problems with the omp but replaced it and no more codes for that but as i hit that speed the problem accurs.... I found several wires of the engine harness damaged which I HOPE is the problem and i Just poke to Ray Crowe and ordered a new one.... Hopefully that will solve it.

Is there an index here for the codes?

 

Sure: http://www.fd3s.net/engine_codes.html

 

Damn dude....that is a hard-core speculatory purchase without knowing exactly what is wrong? You bought the $800 automatic wiring harness without any more input than what you have had?
Have you just simply reset the ECU by pulling the battery cables and pushing on the brake pedal a few times?
It almost sounds like your car was not giving the fuel pump the high-pressure signal. This happened to me once, I had pulled the fuel pump relay and cranked the engine to build oil pressure prior to starting a new rebuild. Car started fine when I put the fuse back in but the ecu thought it needed to be in limp mode.

 

No the car runs and starts fine except the limp mode thing, I checked EVERYTHING and found out that the original harness is in bad shape, tried repairing it but after like 30wires and seemed it would never end i just stopped, plus its something that would of been needed to anyways,

 

Have you tried resetting the ECU?

 

Oh yea several times, the very stange thing is that I have no codes but as soon as i hit about 4000rpms i get codes and goes into limp mode.....

 

Weird
But challenging!
SOMETHING has changed, obviously, from when it ran fine to now. I'd go thru your mental check list and see if anything stands out.
Your wiring issues, while not good, may not be the cause.
Can you GRADUALLY accelerate to 4K or beyond, or does it just go ape-**** right off the bat?

 

It runs very smooth and good until the 4k range than nothing just sounds like im forcing the motor without anychange in speed or rpm. Im also trying to replace the ecu withanother just incase of any damage the harness may have done to it.
This HAS to fix something!

 

Can you see the check-engine light when you first turn the key (i.e. before cranking)? If the CEL isn't working, you might have codes and not know it.

 

yea, and ive been doing hours of dia. and fixed all of them, but they come back as i reach 4k????????????????