Issues with new E316G??

[mnetwork]

I just got the rest of my mods that I've had laying around installed finally (Evo 3 16G, SBR Manifold, Evo 3 O2 Sensor Housing, and FMIC). I was doing street tunes with the installer where I would drive and he would watch the wideband and adjust the S-AFC2. I keep getting boost creep of course and fuel cut. It sems if I go over like 16,17,18 psi I get fuel cut. First time it happened I thought my engine detonated hard or something. Very scary feeling. The tuner put like +5 at the boosting rpm points. Should I need that much fuel added with 680cc injectors? Also, I still feel the car holding back timing and when I hook up the logger I see timing not going much above 9 and 10.

So first.. is the fuel cut normal at these boost points and with the S-AFC setting?

and second, should I be needing that much fuel added? Does anyone else have a similar setup to mine that can share their settings, even if you have different injectors, I'd like to see some S-AFC settings from people with E316G's..

 

[Low Impedance]

are you running stock fuel pump?!?

 

[mnetwork]

Nope, running a re-wired Walbro 190lph pump

 

[Low Impedance]

you might be out flowing the 190.

 

[mnetwork]

I've always been told that a 190 can flow enough fuel to max out any 16g

 

[gixrman]

I don't see a an AFPR listed in your mods. What is your wideband reading?

 

[spyderturbo007]

Fuel cut has nothing to do with fuel delivery, it's airflow related only.

To the original poster:

I see that you have a SAFC-II and 660cc injectors. Are you running a MAFT? How about a logger? I didn't see one in your profile, but I could have missed it. Adding 5% fuel with your setup is crazy. 660cc injectors flow about 31% more fuel than the stock 450's do. So, theoretically, you should be pulling out about 31% fuel to get back to the factory AFR.

 

[CanadianTSi]

Fuel cut has nothing to do with fuel delivery, it's airflow related only.

To the original poster:

I see that you have a SAFC-II and 660cc injectors. Are you running a MAFT? How about a logger? I didn't see one in your profile, but I could have missed it. Adding 5% fuel with your setup is crazy. 660cc injectors flow about 31% more fuel than the stock 450's do. So, theoretically, you should be pulling out about 31% fuel to get back to the factory AFR.

Yep, the +5 on the S-AFC is the reason you are hitting fuel cut.

Get your fuel trims sorted out then drop your high settings to -25 and tune from there.

 

[Mitchel63]

AFC stands for Airflow Converter. When you make adjustments on it, you aren't technically adding or subtracting fuel. You are tricking the ECU into seeing more or less air and then it injects fuel accordingly. So going positive on the AFC tells the ECU that there is more air than there actually is, hence fuel cut. Hope that helps you understand why this is actually happening.

 

[mnetwork]

I totally understand they S-AFC and how it works. I just wasn't sure if I shoud needing that much fuel. My low trims were tuned in the -20's.. but he tuned hi throttle for like +5, I thought that was pretty crazy. I am not running a MAFT, but I do have a logger. I ordered a wideband it should be here this week. I don't have a AFPR because I was told that a 190 didn't need one, that is why I chose the 190 over the 255. I did ask the tuner why I needed so much gas and he said it was because the cold air was so dense that I needed that much fuel... I'm very confused about why he added so much then.

 

[PieEyedPiper]

you might be out flowing the 190.

Definitely not outflowing the 190, at <18psi, especially if it is re-wried - which it is.

I don't see a an AFPR listed in your mods. What is your wideband reading?

AFPR is not required for this setup. But I wouldn't mind having one if it were up to me.

mnetwork,
Listen to CanadianTsi and all will be well

 

[mnetwork]

Definitely not outflowing the 190, at <18psi, especially if it is re-wried - which it is.



AFPR is not required for this setup. But I wouldn't mind having one if it were up to me.

mnetwork,
Listen to CanadianTsi and all will be well

How high would you have to go to outflow the 190.

also.. I really would like to say the S-AFC settings for someone with an EVO 3 16G..

 

[CanadianTSi]

How high would you have to go to outflow the 190.

also.. I really would like to say the S-AFC settings for someone with an EVO 3 16G..

Around 47lbs/min which can't be done with an Evo 3...

Also S-AFC settings are based on injector size and have nothing to do with the Turbo...

 

[mnetwork]

I don't see how the turbo has nothing to do with the S-AFC settings. Of course injectors play the main part, but the more air the turbo flows, the more gas you have to add on the S-AFC. And a person's S-AFC settings would give me the fuel curve at boost and give me a little idea of where I should be. I can't see how I have 680cc injectors and I need to ADD 5+ on the S-AFC. Does this sound like way to much?

 

[CanadianTSi]

Yes +5 is way to much, as I already stated go to -25 and tune from there. When I was running 650's I was somewhere around -33ish.

Also the reason why the turbo doesn't matter is that a bigger turbo will flow more air yes but that air will be measured by the the MAF and the ECU will inject more fuel as needed.

 

[kenamond]

I don't see how the turbo has nothing to do with the S-AFC settings. Of course injectors play the main part, but the more air the turbo flows, the more gas you have to add on the S-AFC. And a person's S-AFC settings would give me the fuel curve at boost and give me a little idea of where I should be. I can't see how I have 680cc injectors and I need to ADD 5+ on the S-AFC. Does this sound like way to much?

The SAFC is just translating airflow so that you get the correct IDC for the larger injectors. I can't say that it's independent of the turbo due to differences in efficiencies, but you should be able to get a good starting point from others running the same fuel setup regardless of their turbo.

Also, since you have a logger, you could use O2v to some extent (until your WB is setup) and timing curves to help fine tune your SAFC.

IT doesn't make any sense that you'd have to add fuel with larger injectors unless you were outflowing your FP or had too low of fuel pressure.

 

[spyderturbo007]

Of course injectors play the main part, but the more air the turbo flows, the more gas you have to add on the S-AFC.

No true. The ECU has what are called maps. When the MAS returns a frequency to the ECU, it looks up a value on the correct map (based on other sensor inputs) and injects the appropriate amount of fuel for the air that has been "injested". There is a lot more to it than that, but that's the stripped down explanation. When you upgrade to a larger turbo, the ECU doesn't care about the turbo, only the additional airflow it produces. With a larger turbo, you will be pushing more air and the ECU will respond by adding additional fuel based on the new airflow value.

See where I'm going with this......?

I can't see how I have 680cc injectors and I need to ADD 5+ on the S-AFC. Does this sound like way to much?

You don't, the problem is that the guy tuning your car has no clue what he's doing. I would run away from that shop as fast as possible. You are probably knocking like crazy with all that fuel. Not to mention all the additional fuel that is still burning when it leaves the combustion chamber on it's way to the turbo.

Follow Tyler's advice and lean the Hi throttle map out to about -25% and make a 3rd gear pull logging TPS, timing, O2, airflow and rpm. After we verify that your TPS value is >95% and consistent, then we can drop that value.

 

[mnetwork]

He said he was going by his wideband, idk. I really didn't get how I could be adding gas. I can't wait for my wideband to come, I'll probably be able to tune this thing perfecty myself between the wideband and the logger.

Oh, and just so I get this correct... If I was to never upgrade my injectors, I wouldn't even need an S-AFC because the ECU would take care of the fuel? Because I was always told otherwise. I was always told that the ECU can only do that to a certain point.

 

[CanadianTSi]

Yes you are correct. If you never upgraded Injectors there would be no need for an S-AFC, although you would max out your stock Injectors pretty quickly with the Evo 3.

 

[oldman]

Don't ever bring your car to this so call "tuner" again!!!!!!

 

[mnetwork]

I was always under the impression that the ecu had limitations and it could only go so far with an aftermarket turbo. So, if I go by what you are saying, if I raise the boost I won't have to adjust the S-AFC?

Also, CanadianTSi you have similar injectors to me and an S-AFC.. what are your settings for Hi + Lo throttle?

Anyway, yeah this tuner seems like an idiot. They are the ones who installed my turbo and intercooler.

 

[oldman]

Anyway, yeah this tuner seems like an idiot. They are the ones who installed my turbo and intercooler.

Oh shit, I would performa boost leak test first before you do anything else.

BTW, Tyler and Nathan are some of the more experience guys I have seen on this forum when it comes to SAFC tuning, you're lucky to have both of them in the same thread.

 

[CanadianTSi]

So, if I go by what you are saying, if I raise the boost I won't have to adjust the S-AFC?

Maybe some minimal adjustments as the increase airflow might bump you to a differnet airflow map in the Ecu...

Going from a Evo 3 16g to a 50 trim my S-AFC settings stayed basically the same, and then adding Cams and a SMIM they didn't really change either.

 

[mnetwork]

So when I raise boost I really don't have to adjust the S-AFC?

 

[spyderturbo007]

I was always under the impression that the ecu had limitations and it could only go so far with an aftermarket turbo.

Correct. When they wrote the code for the ECU, they imbedded an airflow cap for safety. This is the point where the ECU cuts spark based on what it considers to be a dangerous airflow value. For example, if your wastegate were to get stuck closed and you started building massive amounts of boost, the MAS would return a frequency value above this preset limit and the ECU would cut spark to save your motor. The problem for us is that this airflow cap is easy to reach when you start upgrading your turbo.

So, if I go by what you are saying, if I raise the boost I won't have to adjust the S-AFC?

Maybe, maybe not. It really depends on the situation. The higher the boost, the higher the temperature of the intake charge. The higher the intake charge temperature, the more likely you are to knock. So by turning up the boost 2psi, you might start knocking from the added heat, but then again you might not. I know that's not the answer you are looking for, but it's the truth.

What I'm saying is that the ECU will adjust for the added airflow, but you might push your tune over the edge and have to compensate. Like Tyler said, maybe a percent or two here or there. It's not like you are going to have to retune everything.

Anyway, yeah this tuner seems like an idiot. They are the ones who installed my turbo and intercooler.

Yikes! Make sure you leak check like Bruce suggested.

BTW, Tyler and Nathan are some of the more experience guys I have seen on this forum when it comes to SAFC tuning, you're lucky to have both of them in the same thread.

Thanks Bruce, now I'm blushing.