what all is entailed in converting a returnless fuel system to a return one?

 

A return fuel line, has to be metal.

New pump, new pressure regulator.

hmm, thats really all it should need.
YOu will spend most in the getting the pipe costum bent. Or you can try going to a junk yard and taking the return fuel system from and older car.

 

Find yourself a 2000+ accent with the 1.5L and steal its rail, return line, and regulater. Install on your car. Voila, return system. I plan on doing this as i get more money for my turbo project.

 

You guys suck rolleyes.gif I can't revert my 2001 Elantra to the old style sad.gif damn it I want boost......

 

I should think that there would be far more to it that just that. You guys are neglecting to think that the computer controls fuel flow in the returnless system with the signal sent to the pump. How exactly do you plan to 'tell' the car that it now runs with a return? Adding that return line, regulator, rail, pump, etc. does nothing to change the signal sent to the fuel pump by the computer.

 

Why would the pump need a new signal? Frankly, i dont plan on telling the car thats its now running a return line. The main purpose of the return line is to regulate fuel pressure. On the returnless system, the pressure regulator is instead built into the pump assembly. Any electrical connections for the pump will be reconnected, and anything that may affect the regulator would be connected to it as well.

I know its not going to be as easy as it sounds, but I still say that all the parts i'd need are the fuel rail, return line, pump, and regulator.

 

Thats all fine and good ... BUT ... the computer still sends the signal to the fuel pump does it not? The car's ECM was programmed to operate reflecting the returnless system. My understanding of the returnless programming is that it uses different voltage levels to the pump to control pressure. Thus no matter what fuel pump you put in, it will still use the returnless programming to operate unless the car's ECM is 'told' otherwise.

 

But the regulator will no longer be the pump's bitch. the ecm will still send the signal to the pump, and the pump will still pump, but it wont control fuel pressure.

Granted, this all speculation at this point and it would take someone actually trying this to find out for sure.

 

You'd have to look at a wiring diagram for the fuel pump on one of the returnless fuel system cars.

My guess is that there are the usual positive and negative 12V, and then a "reference line" that varies in voltage to tell the pump how much pressure to pump. The "old" style pump should be lacking this connection, so a straight swap should be possible, but the ECU might trigger a CEL. Also, where are you going to reference the vacuum signal off of? The newer intake manifolds do not have the vacuum line going to the FPR as there is no FPR. so you will have to "T" into another of the lines.

 

dont worry random, I will help skierd out smile.gif We got it handled.