Hey everyone, I just finished installing my 25g turbo and 400lph fuel pump. I ordered the STM re-wire kit for the pump, but was hoping to be able to drive it to and from work before the wiring kit gets here. I started it today and it ran fine for 30 minutes or so, then started dying and cutting out (even when pressing on the gas pedal). I am currently at work and can't go look at the car, but I believe the pump has failed due to e85? I have checked couplers and vacuum, and fuses. Any help and advice is appreciated.

*Here is what I know:*
* It starts right up, but will not stay alive
* When the MAF was disconnected, it idled rough, but did NOT die
* Even if rolling down a hill and attempt to put it in gear to keep it alive and "push start" it, will not keep it alive.

*My short term solution:
Put in the stock (or last pump I had) in for now

 

You need to get it tuned.

 

Nope, it was the pump. Swapped back the 255 and it runs fine. I do need a tune for boost however

 

What were the air fuels at idle that pump was probably over running the stock fpr and running rich.

 

On the 400lph? I am not sure. I am surprised I didn't check that

 

If I recall it was actually lean and no gas came out of the return lines when I took out the 400lph pump.

 

I heard with the 400lph if you run e85 it will not work, I thought about getting it, but I'll be running the double pumper for my 700hp set up in the next few years

 

The Wally 400 (part number ending in 262) is not E85 compatible and does have a tendency to die EXTREMELY quickly in high ethanol content.
The Wally 400, a.k.a. 450 or 467 or 475 or whatever else people call it, (PN ending in 267) is designed for E85, is smaller than the 400, yet puts out more volume.

Both of these pumps have a tendency to overwhelm stock returns and cause fuel pressure to spike up to 53+psi or more at idle causing a rather "crappy idle" but will run just fine off idle when the fuel consumption goes up enough that base fuel pressure will be regulated at the standard 43psi.

Since you had no fuel in your return, either your regulator was stuck shut from the excess pressure (which doesn't seem very likely) or your pump was just plain shot from the Ethanol.

If you're going to be on a DD setup and don't want to experience these issues, either run a larger return line (-6AN) so the regulator can return the amount of fuel it's required to, or get a double pumper like the Buschur unit.

If you have any further questions or need to get a replacement pump, return line, or a double pumper setup of your choice (there are at least 3 that I know of), give us a call or PM and we'll get you sorted out.

 

More than likely, the terminals on the pump were eaten away by the ethanol and that caused a huge undervoltage/amperage going to the pump - basically, the pump wasn't pumping.

 

Thanks for the help STM. I will contact you soon to look at possible replacements.