THE E85 HEADACHE

[Dave Laughton]

CURRENTLY RUNNING COBB FLEX FUEL KIT PLUS STAGE 3 WITH A PRO TUNE ON MY 16 STI WITH SUPPORTING MODS. 1000CC INJECTORS, AEM FUEL PUMP (WHICH JUST TOOK A DUMP) COBB EBC, KILLER BEE ELH W/ AN EWG, COBB SRI, COBB CATLESS DP,AOS, TURBO INLET, TOMEI EXHAUST... RUNNING 20LBS

HAVING ISSUES WITH MY FUEL PUMP AND FILTER. LOW PRESSURE PROBLEMS. REPLACING THE AEM WITH THE DW300, IM JUST CONCERNED THAT THIS E85 IS GOING TO CONTINUE TO BE A PROBLEM GOING FORWARD.

TRYING TO KEEP A CONSISTANT BLEND OF 45% ETHONAL, DOUBTING ITS GOOD FOR THE LONGEVITY OF THE SUBI

ANY THOUGHTS, CONCERNS, SIMILAR ISSUES?

 

[Defpo]

I'm sure someone far more knowledgeable than me will be along shortly. How old was the fuel pump when it failed? Still running factory regulator?

My thoughts would be that maybe the regulator sticks open causing the low pressure (I would check the manifold reference line to the FPR for leaks/kinks). this would also likely kill the pump as it will be working much harder to try to maintain normal pressure. Could also just be the fuel pump decided to take a shit and wasnt delivering full pressure before it died completely.

*disclaimer: I dont really know what I'm talking about, just throwing out ideas *

 

[Grinder34]

What do you mean by "low pressure problems"?

Also, I know there are issues with E85 blends. It's possible to have a few E85 tunes and switch depending on grade. I dont know what most people do though.

 

[goldfingerfif]

I see you only have 1 post so I am guessing you signed up and posted and never checked back.

I don't know what you could mean by E85 headache? Doesn't sound like you tuned it as you said you have a protune so if not tuned correctly take it back to the tuner. If you tuned it yourself I can help or suggest possible fixes for any issues.

I would say I have a similar setup without any issues. I don't get low fuel pressure issues; in fact, I run my setup at 10psi higher than stock (53.5psi) mainly for better atomization. I run my car exclusively on E85 with the winter blend going down to about 73% Ethanol is the minimum I run. I haven't had any issues for over a year and a half, my car loves it and I have even changed over to Speed Density now on E85 with some hiccups (this was due to tuning and a new experience for me) but it now runs fine. I believe the coldest it had to start this year was -15 F or -25 C without any issues so not sure but I would like to know more specifics before recommending a solution.

 

[Eagleye]

If the OP is still checking this I'll just add the following:

1. If the flow was good with the protune and you have not changed the tune, I would not look at the tune first but rather why has the flow changed? You mentioned a bad pump, is flow still poor after replacement?
2. Do you have an E85 tester you are using to verify the quality of the fuel you are getting?
3. Is this a DD or does it sit for days between starts?
4. Did you replace the fuel filter when swapping to E85 (or with the new pump)? Has it been checked since having low pressure?
5. How low do you run your fuel level before refilling? Running it low, especially if your fuel quality is questionable and fuel filter status is unknown could have led to the premature pump failure and will likely happen again with the replacement unless some of these things are looked at.

EDIT:
6. I'll 2nd the regulator question, this was the fuel flow issue for my Dad's drag car setup when he switched from race gas to E85 a few years back.

 

[HolyCrapItsFast]

CURRENTLY RUNNING COBB FLEX FUEL KIT PLUS STAGE 3 WITH A PRO TUNE ON MY 16 STI WITH SUPPORTING MODS. 1000CC INJECTORS, AEM FUEL PUMP (WHICH JUST TOOK A DUMP) COBB EBC, KILLER BEE ELH W/ AN EWG, COBB SRI, COBB CATLESS DP,AOS, TURBO INLET, TOMEI EXHAUST... RUNNING 20LBS

HAVING ISSUES WITH MY FUEL PUMP AND FILTER. LOW PRESSURE PROBLEMS. REPLACING THE AEM WITH THE DW300, IM JUST CONCERNED THAT THIS E85 IS GOING TO CONTINUE TO BE A PROBLEM GOING FORWARD.

TRYING TO KEEP A CONSISTANT BLEND OF 45% ETHONAL, DOUBTING ITS GOOD FOR THE LONGEVITY OF THE SUBI

ANY THOUGHTS, CONCERNS, SIMILAR ISSUES?

After you replace the fuel pump, the rest of the setup should support ethanol of any content quite sufficiently. I often recommend the Aeromotive 340 fuel pump with ethanol setups and have seen no issues. Since you have the flex fuel kit, provided you have a proper tune, you shouldn't need to worry about the content at all because the tune will take care of the blending adjustments automatically.

That said, you really shouldn't run into any issues at all from running ethanol. It is actually quite a safer fuel to run provided the tune is correct. See our write-up on E85 for some good information regarding the use of ethanol... https://www.igotasti.com/vBforum/threads/205-All-about-E85.