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Old 04-20-2021, 09:33 AM   #176
OHHFSHO
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Are you tuned for flex fuel? If not you should be...


Yeah I’m tuned for flex fuel.
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Old 04-20-2021, 10:49 AM   #177
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Yeah I’m tuned for flex fuel.
Then you are fine. The sensor will tell the tune how to adjust based on E content. Keep the mix in the "no problem" zone and you should be fine. Maybe try running a tank of just 93 to lubricate the HPFP. Usually that clears up stuttering for folks.

I personally run only 93 towards the end of my oil change interval. e60 the rest of the time. No issues so far.
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Old 04-30-2021, 10:47 PM   #178
andypatterson1991
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Default Similar issue

I've been having pretty much the same issue most of you have been having. I am running a flex fuel map tuned by jestrtuning. I have been tuned for e80 and usually run around 75-78% consistently. I am having bad hesitation towards the end of a gear and my AFR is all over the place. The last datalog I sent my tuner, he said the fuel pressure was all over, +/-300 deviation. I have seen my lowest fuel pressure amount in the 20s before, but that is usually when shifting from one gear to the next, not really while coasting. While driving in the city, I get a random blip where the car reads lean but then goes back to the 14.7 area. I already changed the HPFP about 6 months ago to the Nostrum pump. I also have fresh NGK plugs gapped at .18, as requested by the tuner, and new coil packs. Below is what I think may be the problem, any help or input would be great!
1. HPFP bad again (hopefully not as it's only been in for 6 months)
2. In tank pump is bad or orings/spacers not correct
3. In tank housing assembly needs to be replaced
4. Upstream O2 sensor is bad

These are my engine modifications:
Cobb flex fuel kit
Perrin AOS
Fluidampr
PLM headers with dual Tial external wastegates
iBR BRZ manifold
Nostrum HPFP
AEM in tank pump
Bumper exit exhaust
Mishimoto cold air intake
Turbosmart 50/50 BPV

Car is 2016 wrx
Just hit 100,000
And I have tried it with less ethanol content, e60, e50, and also straight 93 with around 10-15% ethanol content and it does the same no matter what.
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Old 05-01-2021, 06:49 PM   #179
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Originally Posted by andypatterson1991 View Post
I've been having pretty much the same issue most of you have been having. I am running a flex fuel map tuned by jestrtuning. I have been tuned for e80 and usually run around 75-78% consistently. I am having bad hesitation towards the end of a gear and my AFR is all over the place. The last datalog I sent my tuner, he said the fuel pressure was all over, +/-300 deviation. I have seen my lowest fuel pressure amount in the 20s before, but that is usually when shifting from one gear to the next, not really while coasting. While driving in the city, I get a random blip where the car reads lean but then goes back to the 14.7 area. I already changed the HPFP about 6 months ago to the Nostrum pump. I also have fresh NGK plugs gapped at .18, as requested by the tuner, and new coil packs. Below is what I think may be the problem, any help or input would be great!
1. HPFP bad again (hopefully not as it's only been in for 6 months)
2. In tank pump is bad or orings/spacers not correct
3. In tank housing assembly needs to be replaced
4. Upstream O2 sensor is bad

These are my engine modifications:
Cobb flex fuel kit
Perrin AOS
Fluidampr
PLM headers with dual Tial external wastegates
iBR BRZ manifold
Nostrum HPFP
AEM in tank pump
Bumper exit exhaust
Mishimoto cold air intake
Turbosmart 50/50 BPV

Car is 2016 wrx
Just hit 100,000
And I have tried it with less ethanol content, e60, e50, and also straight 93 with around 10-15% ethanol content and it does the same no matter what.
Why is it necessary to run such a high ethanol content, especially if you think that is whats causing the issues (hpfp)? Having said that if you tried two hpfp and issue persists, perhaps it is your lpfp cant supply the hpfp, so again lower e content would help by requiring less amt of fuel. Surely your tuner would have mentioned it or suggested it no?
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Old 05-01-2021, 10:08 PM   #180
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Originally Posted by Rexy18 View Post
Why is it necessary to run such a high ethanol content, especially if you think that is whats causing the issues (hpfp)? Having said that if you tried two hpfp and issue persists, perhaps it is your lpfp cant supply the hpfp, so again lower e content would help by requiring less amt of fuel. Surely your tuner would have mentioned it or suggested it no?
The nostrum hpfp is said to be able to handle the high ethanol content. I've tried running lower content blended with 93 and get the same issue. I'm being told to change the in tank fuel pump assembly.
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Old 05-02-2021, 11:01 AM   #181
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But why is it necessary to go e80? What benefits do you get aside from these issues? Your car can go 150mph but does not mean you should drive it 150mph all the time.

Good advice. Id start there and i suspect nothing is wrong, the lpfp just can't handle the increased fuel demand you face with 80% over 50-60%. Just my guess. That or the nostrum cant handle e80 in practice, whilst in theory on their website it can.
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Old 05-03-2021, 12:20 AM   #182
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Here in SoCal E85 is almost half the price of regular 91. If I had a Nostrum pump I would run straight E85 for that reason alone (and not having to mix it is another bonus)
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Old 05-03-2021, 09:59 AM   #183
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I wouldn't be surprised if the Nostrum pump needs to have the fuel pressure controller gains retuned with E85.
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Old 05-03-2021, 10:17 PM   #184
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I have the nostrum hpfp and Deatwerks 300 lpfp. I put a full take of e85 (sensor said e79) and the next day had cold morning. The car didn’t wanna start. Finally got it to start after the morning warmed up and drove a bit. Was able to get 3gal of 93, brought the content down to e68 and haven’t had a problem since... my best guess is the Nostrum pump cannot handle straight e85.
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Old 05-04-2021, 09:27 AM   #185
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well not starting at e80 could just be bad startup fuel settings in the tune. A lot of work went into cars that came from the factory with flex fuel.
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Old 05-04-2021, 11:02 AM   #186
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Originally Posted by scotte30m3 View Post
I have the nostrum hpfp and Deatwerks 300 lpfp. I put a full take of e85 (sensor said e79) and the next day had cold morning. The car didn’t wanna start. Finally got it to start after the morning warmed up and drove a bit. Was able to get 3gal of 93, brought the content down to e68 and haven’t had a problem since... my best guess is the Nostrum pump cannot handle straight e85.
I’m with you, that was my original assumption. It would be nice not to have to mix due to costs and convenience but what you gonna do when the stutters come for you.

Lets wait and hope we get to hear about the resolution here.
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Old 05-06-2021, 08:03 PM   #187
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Originally Posted by scotte30m3 View Post
I have the nostrum hpfp and Deatwerks 300 lpfp. I put a full take of e85 (sensor said e79) and the next day had cold morning. The car didn’t wanna start. Finally got it to start after the morning warmed up and drove a bit. Was able to get 3gal of 93, brought the content down to e68 and haven’t had a problem since... my best guess is the Nostrum pump cannot handle straight e85.
I've had problems starting in cold weather with any content over 70%. I'm gonna bust into the tank this weekend and check the lpfp out.
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Old 05-07-2021, 07:48 AM   #188
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Originally Posted by andypatterson1991 View Post
I've had problems starting in cold weather with any content over 70%. I'm gonna bust into the tank this weekend and check the lpfp out.


Cold starts with high concentrations of E85 is a know issue. Nothing is wrong with your fuel pump it’s the nature of the fuel. A simple google search will show you this. This is why in winter months the the suppliers change from E85 to E50-65.
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Old 05-07-2021, 12:57 PM   #189
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Cold starts with high concentrations of E85 is a know issue. Nothing is wrong with your fuel pump it's the nature of the fuel. A simple google search will show you this. This is why in winter months the the suppliers change from E85 to E50-65.
If we make reasonable assumptions that its common knowledge that it starts harder then we can assume the tuner is aware and tuned for it, ie compensated by enriching. My fuel trim correction can be 25% in cold startups in am (40-50f). So i would assume that tuner has enrichened the startup and compensated for colder temps but there maybe mech issues with hpfp and high ethanol content, ie you're missing the point as no one is rediscussing common knowledge.

Its a thread about hpfp and high ethanol content performance or lack there of in some cases. I firmly believe that pumps cant handle high ethanol content, period. All the evidence i read points to that. I would not assume a reasonable tuner failed to compensate and address common knowledge. I find it easier to believe that a pump can not deliver or fulfill the request, and to your point at cold startup is when it is taxed by enrichment requirements.. which i assume it is struggling to handle.

It would be easily tested by trying to start the same car on 50% and 75% and see if there is difference.

Last edited by Rexy18; 05-07-2021 at 01:09 PM.
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Old 05-07-2021, 07:16 PM   #190
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Originally Posted by Rexy18 View Post
If we make reasonable assumptions that its common knowledge that it starts harder then we can assume the tuner is aware and tuned for it, ie compensated by enriching. My fuel trim correction can be 25% in cold startups in am (40-50f). So i would assume that tuner has enrichened the startup and compensated for colder temps but there maybe mech issues with hpfp and high ethanol content, ie you're missing the point as no one is rediscussing common knowledge.

Its a thread about hpfp and high ethanol content performance or lack there of in some cases. I firmly believe that pumps cant handle high ethanol content, period. All the evidence i read points to that. I would not assume a reasonable tuner failed to compensate and address common knowledge. I find it easier to believe that a pump can not deliver or fulfill the request, and to your point at cold startup is when it is taxed by enrichment requirements.. which i assume it is struggling to handle.

It would be easily tested by trying to start the same car on 50% and 75% and see if there is difference.


There is nothing any tuner can do in regards to cold day starts and high ethanol content . Unless you have a warmer in your fuel cell and a warmer on your engine it’s not going to start easy.

“The ethanol-powered engine can present problems in cold days because this fuel requires high temperatures to change its physical state and provoke the operation of the engine, unlike gasoline that evaporates quickly”, said Hiromori Mori, Technical Assistance Technician of NGK.

Now, in regards to our factory hpfp yes it’s is correct anything above E30 is a crap shoot. Mine doesn’t have any issues till E50 or higher at WOT. Others can run up to E60 np. The Nostrum hpfp claims its good up to E100 with a 40% increase in fuel capacity over stock. I’m interested in those with the Nostrum and the success or failures they are dealing with.
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Old 09-21-2021, 12:50 PM   #191
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Default Another ethanol issue

This is the only somewhat current thread I could find still talking about ethanol content issues so here goes-
Apologies if I couldn't find a thread that already exists with a definitive answer.



Recently got tuned by Ron Watson for ethanol, '16 WRX with the Nostrum HPFP and DW 300c. All through the tuning process the car ran flawlessly with E content up to 75/76%.
Couple weeks after finishing the tune I was on a freeway on ramp, 4th gear under load and I felt two distinct "hiccups" which I thought might be misfires, no code thrown. Took it super easy on the way home and parked it overnight. In the AM start the car P0087 fuel rail pressure low. Plugged in the AP and fuel pressure was bouncing between 300 and 1200 psi. Shut it down, had both pumps tested, both fine. Ended up replacing fuel filter and car runs fine for week and a half with good fuel pressure until today, start the car as I was backing out felt a stumble, immediately got P0087. Reset code, and monitored fuel pressure and it's stable 8-9xx psi at idle.

With ethanol almost half the price of gas I was hoping to just go full E85 since both Nostrum and DW say their pumps can handle it.

So what gives? Why the fluctuating fuel pressure issues? I was really hoping not to have to mix, that was the whole point of going full e85.
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Old 09-21-2021, 02:58 PM   #192
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With ethanol almost half the price of gas I was hoping to just go full E85 since both Nostrum and DW say their pumps can handle it.

So what gives? Why the fluctuating fuel pressure issues? I was really hoping not to have to mix, that was the whole point of going full e85.
Quote:
Originally Posted by scotte30m3 View Post
I have the nostrum hpfp and Deatwerks 300 lpfp. I put a full take of e85 (sensor said e79) and the next day had cold morning. The car didn’t wanna start. Finally got it to start after the morning warmed up and drove a bit. Was able to get 3gal of 93, brought the content down to e68 and haven’t had a problem since... my best guess is the Nostrum pump cannot handle straight e85.
This has been my best guess as well.
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Old 09-21-2021, 05:03 PM   #193
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Cold weather starts are going to be difficult on E85 and it is not pump related. This is an issue on any car that is on E85.

You need a lot of extra fuel to get the car to fire up on cold mornings. The cold start enrichment tables need to be properly tuned.
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Old 09-21-2021, 06:09 PM   #194
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Cold weather starts are going to be difficult on E85 and it is not pump related. This is an issue on any car that is on E85.

You need a lot of extra fuel to get the car to fire up on cold mornings. The cold start enrichment tables need to be properly tuned.



Right, but the car starts fine, it fires immediately. I am in CA it's over 80 degrees in the AM, and the tuner is one of the most respected in the business. Also the fuel pressure issue seems to be intermittently present after the car is already running and warm. This is the reason I'm seeking out if anyone else is experiencing similar issues with a similar setup and if there is a known fix besides mixing.
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Old 09-21-2021, 11:17 PM   #195
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Right, but the car starts fine, it fires immediately. I am in CA it's over 80 degrees in the AM, and the tuner is one of the most respected in the business. Also the fuel pressure issue seems to be intermittently present after the car is already running and warm. This is the reason I'm seeking out if anyone else is experiencing similar issues with a similar setup and if there is a known fix besides mixing.
ahh...didn't really read your post lol

You might have some intermittent issues. Do you have a fuel pressure sensor on the low pressure side?

Even with the nostrum pump your limitation is how much the factory injectors can flow.
I heard of cars sputtering when trying to run high E content. I've also seen logs of cars that seem to run great on full E but the AFR's are piston melting lean at WOT. That's why mixing is preferred.
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Old 09-22-2021, 06:15 PM   #196
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ahh...didn't really read your post lol

You might have some intermittent issues. Do you have a fuel pressure sensor on the low pressure side?

Even with the nostrum pump your limitation is how much the factory injectors can flow.
I heard of cars sputtering when trying to run high E content. I've also seen logs of cars that seem to run great on full E but the AFR's are piston melting lean at WOT. That's why mixing is preferred.

I don't have a pressure sensor on the low side. It fell off the list of things to buy unfortunately. I haven't heard but is it possible the in tank pump just can't keep up? I am somewhat skeptical of this only because the car has run fine during tuning-several 3rd gear WOT pulls without issue, then has a hiccup in fuel pressure once in 4th gear at around 3krpm and the other just reversing out of a parking space.

I can't really figure it out unless the properties of the actual fuel are in play. I'm only speculating, but the fuel flow characteristics for the car were designed using gasoline, I wonder if the difference in viscosity, weight, etc effect how ethanol travels through the fuel system causing some type of cavitation or surge. I know when I worked in gas and oil there were surge tanks on different types of pumps to prevent this issue.

As you can tell I really don't want to mix, that solution is too easy. Now I'm thinking about surge tanks for a street car. FML
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Old 09-22-2021, 10:50 PM   #197
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I don't have a pressure sensor on the low side. It fell off the list of things to buy unfortunately. I haven't heard but is it possible the in tank pump just can't keep up? I am somewhat skeptical of this only because the car has run fine during tuning-several 3rd gear WOT pulls without issue, then has a hiccup in fuel pressure once in 4th gear at around 3krpm and the other just reversing out of a parking space.

I can't really figure it out unless the properties of the actual fuel are in play. I'm only speculating, but the fuel flow characteristics for the car were designed using gasoline, I wonder if the difference in viscosity, weight, etc effect how ethanol travels through the fuel system causing some type of cavitation or surge. I know when I worked in gas and oil there were surge tanks on different types of pumps to prevent this issue.

As you can tell I really don't want to mix, that solution is too easy. Now I'm thinking about surge tanks for a street car. FML
I'm not saying your LPFP can't keep up but you may have a intermittent hardware issue somewhere.
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Old 09-23-2021, 04:53 AM   #198
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My money is on the bypass in the HPFP, Nostrum or not, sticking open. When I had my FA20DIT on flex I learned to watch my post HPFP pressure on my AP for pressure oscillations during cruise. Once I saw the imperceptible oscillations I would fill it up the rest of the way with 93.

YOU ARE NOT GOING TO BE ABLE TO RUN STRAIGHT E85 WITH NO ISSUES, EVEN WITH AN OEM PUMP THAT NOBODY REALLY KNOWS WHAT NOSTRUM PUT INSIDE IT.

Your reasoning about the cost of 93 is silly. Pay to play.
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Old 09-23-2021, 08:17 AM   #199
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I'm not saying your LPFP can't keep up but you may have a intermittent hardware issue somewhere.
Now that you mention it I recall some people having issues with their DW300. I never did when running E60 or under for 10k miles. Some people have reported that they switched to AEM 340 (? I forget if that's it) and stopped having issues. But most of these were for people running E50/E60 tunes as far as I remember.

I still think that it's just not possible to run E85 through the Nostrum HPFP, and it's not like I ever saw anyone from there on here defending that.
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Old 10-04-2021, 05:47 PM   #200
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Originally Posted by timpala11 View Post
Now that you mention it I recall some people having issues with their DW300. I never did when running E60 or under for 10k miles. Some people have reported that they switched to AEM 340 (? I forget if that's it) and stopped having issues. But most of these were for people running E50/E60 tunes as far as I remember.



I still think that it's just not possible to run E85 through the Nostrum HPFP, and it's not like I ever saw anyone from there on here defending that.


With a hard wired DW300 I run E95–yes E95 for over a year since adding a the Nostrum with no problems other than the typical cold start challenges
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