OK, thinking about swapping a return fuel system on my 04, using a 2003 setup. I know the main thing behind it is money. But let's say I got from an 03 lancer, the:
-intake manifold
-fuel rail
-fuel pump
-return line
Basically all the components for the return system to make it fit my car. Question is, does the ECU play any part in the system, or does the fuel just return on it's own through vaccuum or however it works? Just wondering if the swap would require swapping the ECU as well or not.
Thanks

 

I don't think the ECU has anything to do with it, I don't remember seeing any electrical plugs going to the system on my lancer.

 

You shouldn't need the manifold (isn't it identical for all 4G94s?) and you won't need a fuel pump. You will need the fuel rail, the fuel pump assembly (not the pump) off an 02-03, a FPR, and a lot of tubing. The reason for the assembly is that the one off of an 02-03, or an Evo, will have the fitting for the return line. Otherwise, you'll need to drill a hole in your tank and make one yourself.

 

I think the manifold changed for the 04-06 lancers.

 

Noob question, but whats the advantage of swapping to the older gen fuel system?

 

I was just thinking it would be easier to build your own turbo kit without having to mess with that 5th injector stuff or anything if you have a return fuel line. But yeah, I meant just the part on the pump with the return line, so the assembly. And the manifold is a tiny bit different. Apparently the fuel rail sits differently and won't line up properly with the injectors. I found this out while installing my twin TB manifold from an 03 Lancer. But thanks for the help. I'll probably end up doing this soon then.