I now wiring the back half of my swap. I've swapped the fuel pump from the 03 WRX and Now i'm wondering if i need to swap the fuel pump controller? where is it? and should i swap in the rest of the tank pressure sensors and such? Or if anyone knows of an easy way to pump fuel from a 97's tank into a 03 WRX engine?

you will need FP controller. it is a gray box looking thing. with 1 bundle coming out the "back". should be right by the pump portion of the harness of the WRX. the rest of the sensors can be swapped, but if yours are ok and all there you can skip. i wondered about just hooking up the fuel pump with the 1.8 harness, and just letting the unused pressureized gas recirculate. since the L's use stright voltage instead of variable voltage like the turbo cars utilize. there would be no real problem i can see.

so the whole fuel pump assembly is bolted in from the wrx. It looks like theres a difference in the wiring for the fuel temperature sensor. How exactly does the fuel temperature sensor effect how the car is running? The rear harness of the OBS is missing a wire for the temp sensor. Should i maybe swap the wrx pump into the obs cage? If it will be ok, and i dont have to change any of the other rear tank sensors and such, wiring will be much simpler.

use everything WRX possible. or wire the temp sensor into the OBS rear harness. either way you should go like hell.

oh, are you using the WRX ECU?

yes Im actually using the whole front wiring harness...Everything under the hood and under the dash are from the WRX including the ECU. As it stands now, I think I will have to use the tank/pump/sensor wiring from the WRX. Im not sure if i need to transfer over the "drain valve sensor". But I don't think I need to change that big mess of hoses that can be found behind the Right Rear tire.
This is my very last obstacle before she cranks.

Im still kind of confused about whether or not I will have to swap over any sensors, especially since there is one more sensor on the WRX harness. I'm also worried that I'll have to swap the hoses and such over from the WRX.

You may encounter a couple emissions codes if you don't use the hoses and canister from the wrx. I think a reflash would fix the problem...... AND gain a bit of power.
You will also have CEL if you do not switch the sensors and the controler for the fuel pressure. I have been dealing with all these problems on my swap...... The stock ECU needs the input from all the sensors or you have a nice bright CEL to remind you that you did something wrong.

Indeed, I was looking in the wiring diagram and every single sensor goes straight to the ECU. As long as it will run ok until i can get it tuned, I think I will plug the wrx wiring harness into my OBS sensors and just leave the one that isnt there. I've got the pump controller in now as well, I just need to solder the 97's door, hatch, and rear tail light wire connectors onto the 03's wiring harness and then i can put my interior back together and be done with it....Now if the UPS man can find the kindness to bring me my radiator and driveshaft, I'll finally be able to drive a powerful AWD car.

I'm curious, will a swapped car actually run without the fuel pump controller? Obviously not correctly, I'm just wondering if it will start and drive.

I'm curious, will a swapped car actually run without the fuel pump controller? Obviously not correctly, I'm just wondering if it will start and drive.

Yes, its entirely possible.

But just missing the drain vent sensor shouldn't affect driveability will it?

I don't have a fuel pump controller in mine. It's a Ver8 SpecC with a Ver7 ECU.

Apparently it can run very rich without it (I don't know what my Air/Fuel ratios are) and I can tell from my blackened exhaust tip, strong smell of gas and horrible fuel economy although that may be more of driving "style" thing. :D

I'm curious, will a swapped car actually run without the fuel pump controller? Obviously not correctly, I'm just wondering if it will start and drive.


Yes it will run, the fuel pump will just never stop priming, and you will most likely throw CELs for the lack of the FPC