[paradoxical3]

Hi guys,

I am posting here because I think I am one of the guys who has run a higher amount of miles on N55 engines with e85.

I have a 2014 X1 35i, which uses the same N55 engine and 6at transmission as 335i. It is FBO with Pure Turbo Stage 1 upgrade, and I have been running an e85 blend since 300 miles. So this car has about 57k miles on it in the last 2 years.

I run the car hard, and it has over 20 track days plus a bunch of drag strip days on it. At first, the car could handle a 50% e85 blend just fine. But over time, the amount of ethanol it could supply dropped and dropped. Recently, I could barely run 20% and the car started exhibiting all the classic signs of HPFP failure (throttle stumbling, misfires, etc). Finally, the car shut off on me while driving. It worked fine for one more day, but then refused to start. When you crank it, the engine fires up but runs super rough and stalls out.

From reading codes and other diagnostics, it looks like the HPFP is dead. Unfortunately, it is this pump and I can't find it cheaper than $850 anywhere (http://www.ecstuning.com/BMW-E84-X1_...uel/ES2767579/). Tried to swap in a N54 pump but it wouldn't fit.

Just a heads up. I know these pumps die and that it is a common thing with BMW, but I have to believe that my pumps failure was accelerated by lack of lubrication with e85. I have kind of known it was coming as the ethanol percentage I could run has been dropping over the last year.

I will replace this pump and than am not sure what I will do with the car. Maybe Stage 2 turbo so I can make just as much power but on 93 octane.

[weehe126]

Well yours is equivalent to the F series of N55s. They are known to only be able to handle around E30 at most. I'm actually shocked you were able to run E50 at any point.

[paradoxical3]

Originally Posted by weehe126

Well yours is equivalent to the F series of N55s. They are known to only be able to handle around E30 at most. I'm actually shocked you were able to run E50 at any point.

Indeed it is. I didn't realize this until you mentioned it and I cross referenced real oem.

This is super strange as the X1 is an e84 chassis car and uses the old N55 engine with the pneumatic wastegate. I have no idea why they decided to use a F30 pump on it.

[Euroboost91]

Holy crap! 57k miles in 2 years????

[weehe126]

Originally Posted by paradoxical3

Indeed it is. I didn't realize this until you mentioned it and I cross referenced real oem.

This is super strange as the X1 is an e84 chassis car and uses the old N55 engine with the pneumatic wastegate. I have no idea why they decided to use a F30 pump on it.

That is interesting, but unfortunate. At least you can get a stage 2, run E20 and get low 500whp.

[paradoxical3]

Originally Posted by Euroboost91

Holy crap! 57k miles in 2 years????

Yup, several thousand of those are track miles, about 8k are from doing road rallys with Rally North America, and weekly backroads drives, etc. Driving is my #1 hobby and how I relieve stress.

That is interesting, but unfortunate. At least you can get a stage 2, run E20 and get low 500whp.

I think I am going to do a stage 2 turbo and just run 93 octane for 450whp. I really want to do one lap of america next year and e85 wont be widely available anyway. Will run e85 or 100 octane at the drag strip but daily it will be nice to just use 93.

[weehe126]

Totally agree. 18psi to readline must be amazing.

[paradoxical3]

Looks like I jumped the gun here.

Amazingly, the problem appears to be corrosion of the high pressure fuel rail connector. I discovered that the connector was completely corroded, it looks like moisture was running down the wiring into the connector.

Cleaned out the pins with MAF cleaner and a brush, and the car fired right up. Drove 30 miles today and so far so good.

If you are having problems like steady state fuel cut outs and HPFP symptoms, check your wiring harness!

[weehe126]

Originally Posted by paradoxical3

Looks like I jumped the gun here.

Amazingly, the problem appears to be corrosion of the high pressure fuel rail connector. I discovered that the connector was completely corroded, it looks like moisture was running down the wiring into the connector.

Cleaned out the pins with MAF cleaner and a brush, and the car fired right up. Drove 30 miles today and so far so good.

If you are having problems like steady state fuel cut outs and HPFP symptoms, check your wiring harness!

That's great!

[kevBquick]

glad yours didn't die yet....but it will.

gotta remember the more E you add...the more you make the HPFP work. e40 was the limit. hard miles on e50 will cache out your fuel pump. its not an if.....just when.

[PeterPure]

Tnx for sharing this. I ran e20 with stock hpfp and meth. Now i run E35 with stock hpfp and tbi kit 25 psi no prob

[paradoxical3]

Originally Posted by Darkhold

Tnx for sharing this. I ran e20 with stock hpfp and meth. Now i run E35 with stock hpfp and tbi kit 25 psi no prob

Can you run 50/50 mix with tb injection or can it not flow enough?

[PeterPure]

Originally Posted by paradoxical3

Can you run 50/50 mix with tb injection or can it not flow enough?

I did not test E50 with tbi. My hpfp sucks so bad even with E35 it bails out at 15 psi without meth or tbi. Happy to do 25 psi on E35 with tbi.