Help diagnosing power loss while WOT

[Celica00]

I have a 2017 with the OFT e85 tune, high flow air filter, catless front pipe. Been running the tune for about 1000 miles with no issues.

There's a super long freeway on-ramp that I like to use to have a bit of fun and typically go full WOT through 1st, 2nd, and 3rd gear, before slowing down and entering the freeway.

This most recent time, as I was in 3rd, the car lurched as if I had redlined. I looked and saw I was only at 6k RPM. So I shifted to 4th and gave it only about 50% throttle. Car lurched and lost power at 4k. So I just shifted to 6th and tried to go freeway cruising speed, but the car kept lurching and losing power and struggling to maintain speed. Eventually all the dash lights came on for a couple seconds and the car made the beeping noise as if I had the door open. I pulled over, keeping the car on.

I kept car idling for about a minute, all the dash lights were back to off. I revved it a few times and nothing seemed wrong about the revs, I found a spot to merge back into the freeway with about a 75% throttle first and second gear pull and there were no more symptoms. The car acted normal the rest of my drive.

Is it the tune? Did it go limp for some reason? Or did I fuck something up?

[p1l0t]

If that was the only time it and it's normal now could have just been a little bit of water in your fuel or something. Have you tried it since?

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[Celica00]

I just finished my ride home and have kept it in the garage. No funny smells or anything. I'm going to the store later today and will give it a couple pulls to see if something occurs.

[DarkPira7e]

I've had this happen to me a couple times. Both times it has been the coilpacks on the passenger side, the one closest to the front of the car.
If you manage to get a used one for cheap, it may be something cheap to try replacing.

More than like it's something fuel related. Let us know if it continues after this tank of gas

[Celica00]

I'm hoping it's just fuel related and not the car. There's only 1 e85 station in the state and the fuel ratio can range from ~58%-90% ethanol if I recall. So not really a reliable source. Might just have to go back to 91.

But this car sings on e85 so I'm hesitant.

[humfrz]

Originally Posted by Celica00

I have a 2017 with the OFT e85 tune, high flow air filter, catless front pipe. Been running the tune for about 1000 miles with no issues.

There's a super long freeway on-ramp that I like to use to have a bit of fun and typically go full WOT through 1st, 2nd, and 3rd gear, before slowing down and entering the freeway.

This most recent time, as I was in 3rd, the car lurched as if I had redlined. I looked and saw I was only at 6k RPM. So I shifted to 4th and gave it only about 50% throttle. Car lurched and lost power at 4k. So I just shifted to 6th and tried to go freeway cruising speed, but the car kept lurching and losing power and struggling to maintain speed. Eventually all the dash lights came on for a couple seconds and the car made the beeping noise as if I had the door open. I pulled over, keeping the car on.

I kept car idling for about a minute, all the dash lights were back to off. I revved it a few times and nothing seemed wrong about the revs, I found a spot to merge back into the freeway with about a 75% throttle first and second gear pull and there were no more symptoms. The car acted normal the rest of my drive.

Is it the tune? Did it go limp for some reason? Or did I fuck something up?

Yep, you did it -

You have an E85 tune and there is only one E85 station in your state -

And that station's E85 ratio can vary from ~58%-90% ethanol.

How much of the rest is water? -

Seriously, I'll go with ol @p1l0t 's theory - your car just picked up a bit of "bad gas".

Sorry you messed up your car -

[Celica00]

Originally Posted by humfrz

Yep, you did it -

You have an E85 tune and there is only one E85 station in your state -

And that station's E85 ratio can vary from ~58%-90% ethanol.

How much of the rest is water? -

Seriously, I'll go with ol @p1l0t 's theory - your car just picked up a bit of "bad gas".

Sorry you messed up your car -

2 reasons to make this iffy judgement call: my commute is short and I'm only 2 miles from the station, but mostly because race car.

Took the car to the store and did some pulls. It's acting like normal again.

I'm just going to cross my fingers and hope bad gas was the culprit.

[Lantanafrs2]

I had the same thing happen a couple of yrs ago. Most likely was a bad tank of e85

[Celica00]

Welp. Fuel pump failed from poor fuel quality. Guess it wasn't a bad batch, but a consistent flow of bad E85. It would've been nice to know this before the engine cut off during rush hour on the interstate.

The warning signs were obvious enough, as the engine started stuttering every now and then for the last 500 or so miles, so no one to blame but myself.

Word to the wise (or at least wiser than me): If there's only one E85 station in your state, they don't have an incentive to source fuel from a quality provider.

[Celica00]

Ok.

My new theory is I fried the fuel pump from poor decision making. As every time the car failed and died were on two freeway entrances where there's a fairly sharp and sustained left turn. And apparently, this car (and WRXs) suffer from a factory flaw of fuel starvation when WOT on a hard left turn. I starved it one too many times and ruined the fuel pump.

Going back to E85 for the summer and will avoid having fun on left turns. Worst case, have to replace fuel pump again and it actually is the fuel source. Best case, racecar.

[Brz866]

Originally Posted by Celica00

Ok.

My new theory is I fried the fuel pump from poor decision making. As every time the car failed and died were on two freeway entrances where there's a fairly sharp and sustained left turn. And apparently, this car (and WRXs) suffer from a factory flaw of fuel starvation when WOT on a hard left turn. I starved it one too many times and ruined the fuel pump.

Going back to E85 for the summer and will avoid having fun on left turns. Worst case, have to replace fuel pump again and it actually is the fuel source. Best case, racecar.

That's the issue the Verus fuel starvation door solves. I installed it and have no issues with high g left turns at all.

[Celica00]

Originally Posted by Brz866

That's the issue the Verus fuel starvation door solves. I installed it and have no issues with high g left turns at all.

How long would you say the install took? Any extra interior rattles from pulling things apart in the cabin?

[FR-S2GT86]

Originally Posted by Celica00

Ok.

My new theory is I fried the fuel pump from poor decision making. As every time the car failed and died were on two freeway entrances where there's a fairly sharp and sustained left turn. And apparently, this car (and WRXs) suffer from a factory flaw of fuel starvation when WOT on a hard left turn. I starved it one too many times and ruined the fuel pump.

Going back to E85 for the summer and will avoid having fun on left turns. Worst case, have to replace fuel pump again and it actually is the fuel source. Best case, racecar.

One other requirement for fuel starvation during hard cornering is a tank that is low on fuel. I think it's supposed to be less than 1/4 tank to give you that problem.

Was your tank low every time you took that high g corner?

[Brz866]

Originally Posted by Celica00

How long would you say the install took? Any extra interior rattles from pulling things apart in the cabin?

No extra noise at all you just pull off the driver side rear seat to get to the access patch and ftspeed has a very detailed video about pulling the pump basket out. I took my time and did a pump at the same time but I'd guess no longer than 2 hours and that's really taking your time from start to finish.