Flex Fuel Tuning in HP Tuners, Tuning Series Vol. 7

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[@vielle568]

My cars almost 50 years old and still running strong. I have just got rid of the carburetor, added injectors, flex fuel and an ECU. This video has been very useful. Thank you.

[@GoatRopeGarage]

What you got?

[@shanemiller9307]

Like always great information thank you

[@eduardogonzalez8862]

Installed the AC Delco Flex Fuel sensor on my 2018 Silverado Crew Cab last year and this is what I found. Of course did all the flex fuel changes on the tune, but, it kept throwing LEAN error codes (P0171, P0174). My LTFT/STFT were always lean. My sensor reads Alcohol percentage of 80% which is awesome. GMs Factory Stoich in the tunes for 80% Alcohol is 10.000ish. I had to drop my Stoich to 8.000ish at 80% alcohol and interpolate across Stoich 14.6 0% alcohol to fix my STFTs. Just had to richen it up a notch 😁

[@patrikmarkebro1323]

Really intresting channel. Thanks! Going to watch it all soon, and maybe over and over again, before I start my tuning trip in life. About E85 I woner if you know about SAABs maps, it are sai that the EcoPower runs from 7-21% more from the 1,8t to the 2.3T about 130-250Hp (on standard gas) an at same time as more hp if run on E85. What o they do different, for an example a Volvo 2.xt Flexfuel do not deliver more hp and takes about 30% more on E85. Any idea what SAAB did do?

[@pg925able]

Thanks again for another great video.Just installed a Flex fuel sensor on my 2016 5.3 Silverado. I had a question about the comment you made about the stock injectors 6 mill seconds for the direct injection engines . Are you saying my stock injectors won't suffice for the extra 30% needed if I plan on running straight E85? I changed my Stoich tables and all the other parameters to safely run E85. I put my first tank of 1/2 91 and 1/2 E85 yesterday and I was around 44%. Just making sure I can run a higher Ethanol % on my next fill-up on my stock injectors? Thanks.

[@booostin21psi]

Do you have a video for setting up the ECM after installing a flex fuel sensor to a vehicle that didn’t originally have it?

[@mrdavis1324]

hello just to let you know i have been watching your videos and i like your style. i liked it so much that i bought my own mpvi2 to start tuning my car. i just installed a bunch of parts and need help with some tune advice

[@jameswiz]

Did you create an account on HPTuners website for the forums? You will find a TON of information and helpful people there, who usually reply in under 24hrs. That's where I've posted and resolved 95% of my issues, but the one I'm working on today, is a bit more complex.

[@davidkerry7865]

I have 2005 Corvette with APS Twin Turbo. I just installed a flex fuel sensor and turned on Flex fuel with my MPV2 Pro. I also have an Innovate SCG-1: Solenoid Boost Controller, Wideband Air/Fuel Ratio, I have heard people saying I need to tune to 1.0 lambda regardless of fuel. I have also read people say you need to tune for .7 Lambda for E85. Which is correct ?

[@Batmans_Black_2018_Camaro_SS]

I have a 2018 camaro ss that I'm getting ready to put headers on but I was trying to do some research on what needs to be changed, do you have a suggestions or know what might have to be changed when the headers go on.

[@Will.GM11]

I have a 2011 Silverado that is flex fuel ready and I’m getting the sensor re-activated. I have headers and a cam. Not looking to go crazy, what is the minimum I need to do in the tuning to run e85

[@Sarajoe91]

I have a 17 Silverado 5.3L flex fuel truck. What’s the best flex fuel tune uou recommend? Just try to get a little more power

[@richardstremlow6075]

Have you added a E85 kit to a 2019 GMC or Chevy 1500 new body style with the 5.3 motor? Looking at doing this, and leaving it in the factory running for now. HP tunner says I have to swap out the ECM for a TCM. The factory ECM is Locked so you can’t write or change parameters.

[@mss14380]

When you copy a flex fuel OS over to 4th gen camaro, how can you get the vin to match so the airbag and service vehicle light will go out?

[@watchman1982]

Is this system able to make automatic adjustments based on lambda or some other method? I have a 2016 F150 3.5L Ecoboost and there is no direct fit E85 sensor (tmk) and therefore no way to determine ethanol content of fuel in the tank. I plan to upgrade the in-tank fuel pump, HPFP and injectors.

[@920PC]

Interesting that it only goes to 80% ethanol. I have a theory as to why that is. Perhaps because when the sensor is initially calibrated it is stated that the fuel in the tank is required to be E10 or lower. It is rare these days to find gasoline without 10% ethanol so the baseline of what the pcm considers pure gasoline is actually 10% ethanol; making the sensor good to up to 90%. I am looking to ADD a fuel composition sensor to my 03 silverado and I believe you said you did that too. Video request. More info on how to do that and if I can get a lower cost sensor (maybe a generic) so long as it outputs the proper signal (hz?)

[@hassanabas1549]

If I am doing c16 or any other fuel with a car that already have a flex fuel sensor is it the same process ?

[@Gt_Rickshow]

Have you heard of ProFlex commander? if you have , what do you think about it?

[@jameswiz]

I need help. I have a 2000 silverado of which I've pulled the 5.3l and installed an "Iron Block LS2" with 36lb injectors, 58psi return less fuel rail, Drive By Cable, with added flex fuel sensor. My P01 ECU was flashed with a 2002 Tahoe L59 (5.3l flex fuel) tune, so I could have those features, plus keep the drive by cable setup. I currently have the flex system disabled and am working on getting the regular gas tune right, but I'm fighting a lean issue, and some knock... The ECU is pulling 2-3degrees under load, running on 93octane. Starting as an LQ9 6.0L block, with 0cc flat top pistons, Gen4 rods, 243 heads, double valve springs, Cam is a TSP220r w/ 0.600" lift on Intake & Exhaust, Headers, cold air intake, and TBSS manifold. I've got it to where it starts easy hot or cold, idles "pretty" well, (some chop, but that could be the cam) doesn't fall on its face under accelerate, and very rarely stalls. It "sometimes" does after a quick throttle hit, followed by fully lifting off, smashing the brakes, and turning the wheel. With that said, it's running too lean for my taste, and I can't seem to fix it. Since this is Gen3, and a Tahoe Tune, I don't have Speed Density available. My wide band shows 14.4-16.5afr anywhere from idle to 2500 under 15% or less throttle and light load. It spikes to 17/18 under 50ish-% throttle, and it's still to new for me to hit PE at 90% throttle... The stoichiometric in the ECU is tuned at 13.5, but my AFR gauge reads as stated previously, and running logs show LTFT is pulling 8-9% on both banks.. I'm not sure how to fix this. Plus (not that it should matter, but I'll say it anyways) when I get upto around 65-70mph at 2500rpm and "coast" AFR will jump to 18 or higher, with a downhill "coast" jumping over 20, which is where my AEM gauge stops measuring.. DFCO is still ON, and if I'm right, seeing high numbers on coast is not dangerous correct? Any thoughts on getting this thing to run a little richer, which may also help with knocking in this case? Thanks

[@FredRTP96]

How much timing is recommended for FBO 5th gen 5.3

[@mandoo414]

hey so basically if i get hp tuners that comes with the adapter (sorry can’t remember the word lol) I can access the air/gas data? I bought performance injectors and coils, (comes with copy and paste data so i’m guessing in good to go after it’s pasted into the tuner? lmk guys

[@tylerlistebarger8943]

i just got hp tuners to learn how to tune on my 2011 silverado. its been tuned by pcmofnc previously for a cam and other bolt ons. but when i opened vcm scanner my fuel trims are in the 20's on bank 2 and around 12 on bank 1. which i know isn't right. i haven't got a wideband yet to see lambda yet but i do plan too. Either way even with out the wideband yet i still don't see why it would show so lean on the fuel trims. My only thoughts are that maybe sense i'm running E85 in it right now (it is a flexfuel truck) and it wasn't tuned while i was running e85 it had 93 in it when i had it tuned so maybe sense E85 requires more fueling the truck is just running lean due to not being tuned on E85 yet. That or im thinking my o2's could be bad. Any thoughts?

[@jameswiz]

Can you please add a link for the video where you added flex fuel plz?

[@askkmb]

What if you have a good 93 tune and don't have ethanol content sensor, but you want to run e85. Do you just multiply fueling tables by roughly 30% and tune from there or say put the stoichiometric table to 9.765 and tune from there?

[@GoatRopeGarage]

Exactly!

[@jacoe33333]

You have any experience of tuning a 5.7 tundra flex fuel ?

[@hassanabas1549]

So we basically do nothing if it has a flex fuel sensor?

[@ashliegadbury6141]

I have a p59 ecm with 3bar os. I see a few tables but nothing like your newer ecm. Do you have any guidance on what all needs to be adjust for this unit?

[@GoatRopeGarage]

I'll have to look at an E59 and see. What are your doing it on?

[@dalehally9871]

With a new freshly built engine which will only running e85. Is it safe to run engine in with e85. I hear some tuners say run in on 98 and if that is true what is the facts to this. Thanks

[@zerofactorx]

So if my truck didn’t have the alcohol content sensor or the wiring for it will it be able to log the pid even if I wire it into the pcm. Currently it shows 0.0 on that pid but I know I should see some alcohol (e10 fuel) unless it’s not able to see it

[@GoatRopeGarage]

You have the PID and it looks like the ECU for that year has the option in the flex fuel tab so even if you don't have the harness already you should be able to track down the pinout to add it. My guess is someone has done it so a little searching on the forums will most likely turn up a write up for you.

[@THEmadmikeismad]

Do you have a video for fuel delivery (pump gas)? After watching your series for maf/map tuning I've learned more than I did in weeks searching forums and youtube. I don't even want to attempt that for fueling.

[@GoatRopeGarage]

What part of fuel delivery, fuel delivery is a calculation of the MAF/SD, it's a constant with the air being there variable that is used to get the final fuel command

[@THEmadmikeismad]

@@GoatRopeGarage I think I found what I was looking for, I just didn't know the name of the table at the time. The power enrichment tables. I was trying to figure out what controlled commanded AFR. My car was going as rich as 11.5 as soon as it was in boost until 5500rpm, 10.8 after 5500rpm. That was taking my stock injectors to 103% and fuel pressure was dropping to 52psi even though 65 commanded. I'm going to finish the map/sd cal and then lean out the pe table a touch and see if that helps until the new parts get in. I actually found the table name through your video, thanks to google. Pretty simple in hindsight, just figured it would have had a fancier name or several tables to edit lol. Thanks for the reply.

[@GoatRopeGarage]

11.5 is about where you want to be on a boosted application unless it is a gen 5, so you might be stressing your injectors, just be careful!

[@THEmadmikeismad]

@@GoatRopeGarage it is definitely stressing the injectors. I was amazed by how rich these run out of the box. As soon as I can get this map dialed in, I'm going to start leaning out the PE table a couple points up top. That will hold me over until the new injectors get here. The map/speed density stuff is such a pain though lol. There's a spot at 1300 RPM/130 KPA that absolutely will not richen up. No matter what I do it's always showing 20% too lean in the log. Once I get that block figured out, it's pretty much done.

[@CarportGarageDragRacing]

If I am wanting to run flex fuel on my 0411 P01 PCM, do I just do the compare, segment swapper, then just choose Fuel System. I will be using the 2002 Tahoe OS IIRC 12216125.

[@GoatRopeGarage]

Yeah, the hard part is finding the right os to do the season

[@whikidfmj]

Ok so I've got an issue here. I've got a gen4 L9H 6.2l Flex from factory. I've been tuning on gasoline for years yadda yadda I'm good with the set up in terms of fueling changes and spark. I decided to finally tune a bit on a 40% mix of e85. Well. I added the fuel, My "virtual flex sensor" (I know not a real sensor) is not switching the fueling? It shows its scaled to command a 12.4 afr in vcm scanner....... but my wideband is showing 14.7ish still... ive idled it drove it light Steped in just a touch idled more. It will not add the extra fuel commanded? Stays at its happy ass fuckin 14.7 I switched my gauge to read lambda and it's sure enough... at 1.00 Is there a way to force it to add that fuel or do I just have to drive horribly lean till it decided ls to add that fuel its commanding? Hope I get some sort of answer I fuckin hate contacting htp. I mean litteraly everything in flex is turned on.. its showing a 41% alcohol content. And it's commanding 12.4 at normal operation. But my physichal gauge is showing 14.7(ish) Just will not physochaly add the commanded fuel increase. Far as I know I've never fucked with any of my flex settings.. ive zeroed my flex map in spark table to cause less interference in my main tables (zeroed alot of em so just relys on my main tables) I had to have switched or shut somthing off aling the way that allows it to physically add the extra fuel? Or does virtual flex see the changes quickly but not compensate forever

[@8gomerpyle22]

If this guy had his own tuning school, i might quit my job and attend it.

[@steve1714]

Hi, I already have a great cam gas tune. If I understand correctly, by adding a flex fuel sensor I can enable the sensor and leave all other flex fuel alcohol tables as per factory settings? Will e85 typically take an additional 6 degrees timing at wot n/a ?

[@GoatRopeGarage]

Yeah, look at the adjustments on a stock flex fuel vehicle, they will carry over as they are compensation for ethanol

[@steve1714]

Thanks. It seems to run a little leaner at WOT with e85 when looking at the o2 voltages. Any tips to richen it up without adjusting the VE table?

[@oddball0045]

You're speaking the truth about the varying alcohol content at the pump for E85. One station can be E85 and the other might be E50. I had a little 93cc scooter with about 13:1 compression running E85 on a carburetor converted to run E85 and i blew it up one day driving down the road because the 7/11 i filled up at was only putting out 60% ethanol in their "E85" and of course being tuned for 85% it started spark knocking and destroyed the rod bearing. Piston looked like someone hit it with a shotgun. Moral of this story, if it can happen to a scooter it can happen to any motor and your tuning window gets smaller and smaller as boost and compression ratio goes up. Imo its not even worth running pump E85 with out an alcohol sensor to variably adjust the spark and fueling or else your motor is just a ticking time bomb

[@GoatRopeGarage]

Exactly! If I'm not mistaken it only has to have 50% alcohol to be considered E85. I worked at a truck loading rack back when they first started blending it and places like 7-11 could request a certain blend in order to hit a price point for the fuel so if they wanted to sell it for $1.99 a gallon they could request the blend amount that would put their cost and price at the right area and as long as it had that minimum of 50% it was considered "flex fuel". Good story, thanks for sharing it!

[@thomasjohnson1142]

Hey bud I’m stumped in between E85 or 93 octane tuning I’ve always ran 93 I haven’t been down the e85 rabbit hole I’ve watched the videos you have on it I have a 2011 GMC Sierra so it’s set up for both I’m just at a fork in the road I’m about to be tearing the top end off in a few weeks so what’s your opinion on it? Help me ! Lol

[@GoatRopeGarage]

It's kind of a double edged sword, it's detonation resistance is great for forced induction but the fact you need 30% more fuel can be a pain unless you're upgrading your fuel system anyways. If so I'd build in enough capacity to cover the 30% at your desired power level so you can run it. From a pure performance standpoint E85 is the way to go.

[@thomasjohnson1142]

I had a feeling you were going to say that I guess I’m just a little A timid dated not knowing much about it I’ll definitely dive into go and finish up your other videos thanks for getting back brother I’ll check in on y’all tomorrow

[@bravepixil]

so if I didn't change the Stoich AFR table and copy my EQ ration from gas to alcohol and let's say I'm shooting for 0.75 lambda on my turbo ls truck, is it ok to do it like that?

[@bravepixil]

it has E38 ECM and its already setup form the factory for Flex Fuel and i will install a flex fuel sensor.

[@flexer83]

Unfortunatly my car cant run full e85, But Lets say the car is fully tuned for e60. In this case can i run any E percentage (example e40) on the vehicle or should i stick to e60 ?

[@GoatRopeGarage]

Stick to E60, variation from it will make you run rich or lean.

[@iVitalzHD]

So when you add timing how on the multipliers how do you know how much timing is being added when you’re not at e85? If you tune on e85 then you’re on e50 later won’t you have the same amount of timing based on this multipliers? Shouldn’t there be a spark multiplier just like a fuel multiplier at a given percentage of ethanol?

[@yousefhamed]

blending takes care of that, if you tune the e85 tables and you have e50 blending takes care of that, but i come from the access tuner world so not sure what it is called here.

[@DM-qp7do]

I bought a wrecked 07 Silverado 2wd 5.3 flex fule at the auction, I fixed the body and when I drove it I think it had regular gas in it cuz it pinged BAD, I put E85 in it and it woke up and runs a lot better but it still had a little pinging to it, I think it has been tuned wrong by someone. Since its a salvage I don't know who owned it before me so I don't know what he did but its almost like he put way too much timing in it, if anyone has any ideas I'd sure appreciate it. Its a really clean truck but im nervous to do any tuning myself because I don't know whats been done to it.

[@hillbillyhicktowngarage5293]

Need to go in & reset the flex fuel sensor, if its over 10% u will have drive ability issues

[@BigMatt302]

So when tuning fueling on e85, is it the same process you outline as tuning on 93 in your maf tuning video? ie turn of 02, disable ltfts ect.

[@GoatRopeGarage]

If you're doing it on a non flex fuel car you can go ahead and adjust your stoich table then do the standard tuning steps

[@BigMatt302]

@@GoatRopeGarage Ok so on a flex fuel vehicle, I did your maf tuning steps and got that all dialed in. I'm a little confused on how to tune the fueling before spark. Does the computer compensate automatically for the ethanol content? Mine seems to be running quite a bit richer than with just 93.

[@GoatRopeGarage]

@@BigMatt302 Yes, you have to dial in the MAF and the SD tables to get it squared away. Are you running rich whole doing SD?

[@BigMatt302]

@@GoatRopeGarage I haven't done SD tuning yet with the ethanol. I'll try to get some logs in before the live stream tonight

[@hassanabas1549]

What about if I am runing let's say an na setup with a 14.7afr on 95 octane already tuned and then I decide I want to run it with c16 fuel do I go tune maf and ve and timing again or my stoich afr commanded will just do the math because now I have c16 in it will change by itself from 14.7 for gasoline to whatever c16 recommend afr runs on ? And if that's so it's a street/race car I am not going to run c16 daily am I going to save these two tunes separately like c16 tune and 95 tune and reflash them whenever I have a race to run c16 tune then after the race reflash my 95octane tune or I am missing something here

[@hassanabas1549]

And how it's different for forced induction platforms

[@yolofullsend]

Is it safe to add the standard e85 timing adjustments on a boosted engine?

[@GoatRopeGarage]

Yeah, I ran them on my truck when it was boosted, just don't get too carried away

[@nickmahramus5034]

Wait so if I understand if you have a solid Tune and VE table for 93 you can just turn the sensor on and adjust timing for E85 no need for fueling changes? I have a 2011 camaro SS with the flex fuel sensor install and it already has a tune on it from a shop but I’ve decided to try to fix the surging issue myself.

[@GoatRopeGarage]

Correct, the stoich table adjusted for ethenol content from the flex fuel sensor reading

[@nickmahramus5034]

@@GoatRopeGarage so i opened up my files for the first time last night and the tuning company turned it on and added 6 degrees of timing across the board on the flex fuel table in spite of the fact they said they didn’t. I also found out the low octane table was the same as the high octane. How bad is this? My VE table also has some ridges so when my AEM wideband comes today hopefully I can smooth that out. Trying to fix the surging issue of my big cam LS3

[@GoatRopeGarage]

It's not the worse, just don't like to do it because you're not protected from bad gas. Ve table can have some ridges, the zones interpolate, do verify it with a wideband when you can

[@nickmahramus5034]

@@GoatRopeGarage I’m going to follow your video on gen 4 VE tuning to isolate the table and see there’s a lot of sharpe edges on this table

[@nickmahramus5034]

@@GoatRopeGarage I’m wondering if I have an exhaust leak or something near the sensor because the graph reads 111% lean at 2 lambda, it’s 42.7% E85. That or I didn’t set up the EQ ratio error graph right.

[@1diybrotha]

So basically your saying that direct injection(is what I have) has a 6ms windown an I cant flow enough for E85? I have a 17 camaro SS LT1, an the kit for it. If this doesnt work, whats next?

[@NickParedez]

Have you had this answered already?

[@1diybrotha]

@@NickParedez No.. I think it was the answer was just trying to confirmed, I should know in a week thou, My kit will be on then.

[@NickParedez]

@@1diybrotha correct, from my understanding, he wasn’t saying that you don’t have enough fuel, or that you won’t, just that during your tuning if you see your average pulse width hit or exceed 5ms you have ran out fuel and will need either a secondary fuel source or a cam with a bigger fuel lobe.

[@GoatRopeGarage]

You might have enough for E85, there is some space usually, I didn't start to run out of injection window until going over 7 psi of boost

[@zerofactorx]

Is there a PID for injector duty cycle or is there a custom set up for it

[@GoatRopeGarage]

It will be injector duty cycle if it's port injection, it will be pulse width for direct injection.

[@GoatRopeGarage]

I haven't verified this math, but you can try it. I'll verify it next time I get a chance. INJDC% = INJBPW * RPM / 1200

[@zerofactorx]

There is a predefined math. Injector pulse with [50112] Engine speed [50070] Expression: [50112.249]*[50070.56]/2*100

[@GoatRopeGarage]

I thought there was something but I couldn't remember, good find!

[@zerofactorx]

So in order to make this work do you have to make a graph of this or can you actually build a pid to make this work