Hi, i recently rebuilt my setup back to stock dpfi on my 91 civic ED6. I had a OBD1 setup and blew my engine now brought back to stock so i can pass smog. Anyway i finally got it running, however it is redlining as soon as i fire it up. Vacuum leaks are hard to check for because i SHOULD NOT be keeping a fresh engine redlining. I checked for crossed wires throughout the harness and TPS. And Nothing. Any input on this from anyone with experience would be great thanks!

 

did you switch the 2 outer wires on the TPS like it was when it was DPFI?
dpfi and mpfi TPS sensors work in opposite directions

 

In my opinion a false sensor reading gives you a check engine light and a cel code.
The engine need fuel and AIR. With a false TPS reading the ECU would probably go in to limp mode and try to keep it running with a safe fuel injection and ignition timing.
When I read your problem correct it starts reving as soon as it starts. This means the engine gets air sucked into it. All sensor read this and accordingly injects fuel and adjusts the ignition timing.
I'm thinking there is something wrong with the throttle cable. Even if you have an air leak in the vacuum hoses it would only make some more revs. Not trying to blow itself up.
But if you want to check for vacuum leaks, a good way to do this without the engine running is to take of the air-filter box or ideally the tube connecting this to the throttle body. Then take a air-pistol or tyre-inflater, stick it past the butterfly plate of the throttle body and put an old, or new doesn't matter, rag in there to seal as much as you can. Then simply apply pressure and check for air coming out of places it shouldn't. But please make sure you dail down the compressor to a max of 14 psi or 1 bar or it could blow of pipes and hoses which are not used to that force and you will end up with more to fix then to begin with.
I hope this helps you out a bit. Please keep us informed on your progress