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Discussion Starter #21
People having high rpm lean issues have nothing to do with the injectors. It's because they are dropping fuel pressure with the factory fuel pump.
that wasn’t the point. Higher rpm even with less boost requires more CC/min of fuel.
 

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I was about to start posting actual logs I've taken showing IPW DROPPING past peak power, but you are all over the place with your points and basing them on opinion instead of facts so we'll just agree to disagree. Good luck with your build.
 

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Discussion Starter #23
I was about to start posting actual logs I've taken showing IPW DROPPING past peak power, but you are all over the place with your points and basing them on opinion instead of facts so we'll just agree to disagree. Good luck with your build.
Your responsding to posts that where to other individuals comments and not yours, that i am not sure what they had to do with what we where originally discussing. So i can see how you’d think it was sporadic.

you have a log of injection duty cycle from 4k to redline? Showing duty cycle decreases from around 5,500 to redline?
Also logging boost and AFR to correlate.
 

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Discussion Starter #24
To sum up and get on the same page. correct me if i am wrong.

You believe injector failure is primarily caused by ethanols corrosive characteristics either breaking down something in the injector and/or causing the fuel rail to “chip” small metal peices off clogging the injector?

and I believe either
A. The stock fuel system has an inherent issue stock regardless of fuel type and you just get unlucky.
B. Contaminants are introduced into the system when changing HPFP which is typically for E85, so correlation doesn’t equal causation.
C. Injectors are essentially burning out from being maxed out too long once running higher boost/power in addition to E30+
D. Stock fuel rails can’t adequately handle the pressure and flow rate of the aftermarket HPFP causing the metal “chipping”

and the majority of injector issues have little to no cause because of ethanol’s corrosion characteristics.

Do I have 100% difinitive proof of any of this, no not really.
Do you have proof to the contrary?

But modifying and tuning many older and same year platforms I really haven’t seen ethanols corrosion characteristics be the cause of a fuel system failure, maybe in much older platforms, but not recent year. It would be odd to have it be a somewhat unique issue on such a new/modern higher end platform. But i could be wrong. My experience with this specific platform is currently limited and I’m still researching it and learning.
 

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Your responsding to posts that where to other individuals comments and not yours, that i am not sure what they had to do with what we where originally discussing. So i can see how you’d think it was sporadic.

you have a log of injection duty cycle from 4k to redline? Showing duty cycle decreases from around 5,500 to redline?
Also logging boost and AFR to correlate.
You are posting in a forum my friend, even if you are discussing with me people are free to jump in and add their own input this isn't a one-way conversation.
 

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Personally I'm leaning towards a combination of points A and D, more so A and I think the higher flow rates of fuels be they mixed or not
simply exasperates the issue.

Inifniti wouldn't put out a TSB unless there was a fair number of cases.
 

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I believe it's a combination of higher Ethanol fuel content and your letter D. AMS seems to agree with this, except they seem to throw in the phantom "contamination". I do not believe that dozens of people, using highly qualified shops ALL were so dirty that doing a simple fuel pump swap caused their systems to have so much junk in them that they kill the injectors. To my knowledge there hasn't been a single person whose swapped fuel pumps and ran E content that hasn't had an injector failure.

FWIW I've been tuning other platforms for over a decade at higher power levels than were talking here so I'm no spring chicken either lol.
 

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Discussion Starter #28
You are posting in a forum my friend, even if you are discussing with me people are free to jump in and add their own input this isn't a one-way conversation.
Wasn’t my point.

Me and him having a discussion about 1,2,3

Me and you having a discussion about X,Y,Z

he responds to a comment from me to you about X,Y,Z and says i am jumping around. I was just pointing out it looks like “jumping around” because that post was directed to you not him. But either of you are obviously more then welcome to respond to any post. Just make sure you are aware what the original post was a response to is my point otherwise it starts getting confusing.
 

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Discussion Starter #29
Personally I'm leaning towards a combination of points A and D, more so A and I think the higher flow rates of fuels be they mixed or not
simply exasperates the issue.

Inifniti wouldn't put out a TSB unless there was a fair number of cases.
So my conclusion is if it is A. Then unless you want it fixed under warranty going Ethanol you are no worse off.
or if its D, using stock HPFP only using E30 and on slightly lower boost you should not be at greater risk because of ethanol.
 

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Discussion Starter #30
To my knowledge there hasn't been a single person whose swapped fuel pumps and ran E content that hasn't had an injector failure.

FWIW I've been tuning other platforms for over a decade at higher power levels than were talking here so I'm no spring chicken either lol.
Do you mean you don’t know anyone who swapped HPFP using no added E% who has had a failure?
or every single person who swaps fuel pumps and uses higher E% has had a failure?

you probably have more experience than me. but In all other platforms I’ve dealt with ethanol has always been the holy grail of fuels. As good or better than race gas only downside is fuel efficiency and often needing larger pump/injectors to compensate. No issues with corrosion though.

So if fuel rail seems to be a big contributor to the issue. Does anyone make or is anyone working on making an aftermarket fuel rail to resolve this?
 

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Discussion Starter #31
Are AMS injectors somehow not effected by the fuel rail chipping issue? They have large enough injector opening the metal just passes through?
 

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Do you mean you don’t know anyone who swapped HPFP using no added E% who has had a failure?
or every single person who swaps fuel pumps and uses higher E% has had a failure?

you probably have more experience than me. but In all other platforms I’ve dealt with ethanol has always been the holy grail of fuels. As good or better than race gas only downside is fuel efficiency and often needing larger pump/injectors to compensate. No issues with corrosion though.

So if fuel rail seems to be a big contributor to the issue. Does anyone make or is anyone working on making an aftermarket fuel rail to resolve this?
Every single person who has swapped the HPFP and used E has had a failure to my knowledge.

And I am ALL for E85....the stuff is magic. It's darn near impossible to blow up a motor with it. This platforms fuel system just doesn't play nice with it.

I don't believe anyone has an aftermarket fuel rail, but if you purchase AMS injectors I think they offer a factory replacement that likely has some cleaning or deburring or something.
 

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Quote:
"Notes
In order to take full advantage of the Red Alpha Kinetic Direct Injectors, specific calibrations to your ECU tune file will need to be made. Once the injectors are installed, an appropriate ECU calibration must be loaded before the engine starts and runs or damage can occur! Please contact an AMS sales representative to discuss your ECU tuning needs by emailing [email protected].

Fuel rail replacement is highly recommended. Please see OEM Injector Failure statement below for more details.
"
 

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This thread is about to become a trainwreck ... let's answer the question: maximum safe ethanol content: 10%. The owner's manual states this value and many fuel pumps across the United States have up to 10% ethanol mix on their 91 and 93 octanes.

If you upgrade the low pressure fuel pump, high pressure fuel pump, fuel injectors, and replace both fuel rails [with the newer build years], you may be safe to run up to E85; however, as with any flex fuel setup, you should cycle pure octane often.

If any single one of those components is not upgraded [replaced in the case of the fuel rails], ethanol mixes above 10% are not safe.
 

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Discussion Starter #36
This thread is about to become a trainwreck ... let's answer the question: maximum safe ethanol content: 10%. The owner's manual states this value and many fuel pumps across the United States have up to 10% ethanol mix on their 91 and 93 octanes.

If you upgrade the low pressure fuel pump, high pressure fuel pump, fuel injectors, and replace both fuel rails [with the newer build years], you may be safe to run up to E85; however, as with any flex fuel setup, you should cycle pure octane often.

If any single one of those components is not upgraded [replaced in the case of the fuel rails], ethanol mixes above 10% are not safe.
Owners manual says 15% not 10%,

and this is most likely for liability reasons and because it does not have a factory flex fuel kit. they wouldn't recommend using say E30 because that requires mixing and do not want the liability of people mixing incorrectly, and the car doesn't have a factory flex fuel system to accommodate various E%. This is standard in most owners manuals for cars with out flex fuel kits. It does not indicate incompatibility, as most modern cars once fitted with a flex fuel kit/tune run full E85 with no issue. Depending on boost levels it appears the stock fuel system can supply the engine with enough fuel going up as high as E30 but that is pushing the limits especially on high boost tunes. The pumps, hoses, injectors, seals etc.. are all ethanol compatible. The only potential issue is with the fuel rails.

Are you saying they revised the fuel rails in newer years to resolve the issue? is it a different part number?
 

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Are you saying they revised the fuel rails in newer years to resolve the issue? is it a different part number?
Same part number but new batches; Infiniti themselves state (ITB17-035) that the fuel rail must be replaced.


The pumps, hoses, injectors, seals etc.. are all ethanol compatible. The only potential issue is with the fuel rails.
Nope, nope, nope. I am checking out at this point; it is your car and your money, feel free to destroy it because you are not fucking listening or thinking.
 

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Answer is, 'safe' levels is the ethanol included from the pump when using regular octane gas. Any e blending and YMMV. I've seen people run e30 on stock pumps no problem, I've seen people install the HPFP and blow an injector on 93 before they could even add E. I've also seen an injector blow on stock pumps, 93 only. No 2 cases are similar. The moment you add E, you are at an inherent risk of something failing.
 

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Discussion Starter #40
You seem hell bent on inferring what everyone's intentions are from AMS to Infiniti themselves. It's your car and your $, have at it.
When did i state anyone's intentions?

As you even suggested the main issue is the fuel rails.
If that is the case i don't see why changing LPFP, HPFP, injectors, and using new factory fuel rails (unless they revised them?) would change the fact that the fuel rails will still fail? Maybe even at a faster rate with HPFP.
Changing LPFP,HPFP, injectors just allows the system to flow enough fuel to accommodate higher ethanol% and/or boost levels, but doesn't change the compatibility of the system, only prevents it from going lean. but going lean isn't an issue with low ethanol and lower boost. so it seems ethanol regardless of what is changed can never be done safely as @Malmby suggested?

unless ams injectors are not effected by "chipping" fuel rails for some reason?
or the oem fuel rails where revised in later models?
 
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