Weird table modifications while tuning VVE

[imgarten.fredrick]

I am having some really really odd things happen with the VVE editor. I will paste in my percent correction to the table like usual and then I will press "calculate Coefficients" and then it makes a huge hole in my table. the numbers go negative.

I'll attach the files below. I cannot find any answer or where this has happened to someone else.


copy the STFT and paste into the VVE "multiply percent" not half. See if it gives you the same results as me

[GHuggins]

Worked fine for me using x% in beta and 3.4's latest update... How do you have your stft error setup?

[imgarten.fredrick]

Worked fine for me using x% in beta and 3.4's latest update... How do you have your stft error setup?

I am using the fuel trim percents.. Off of a guide I've followed on here. DFCO, COT, LTFT's and MAF off. Staying out of PE. My table axis's are the same for the VVE table. I may try to re install HP tuners. I get the fuel trims close to where I'd start going by halves at +-5. When I update the table, it just throws my fuel trims completely off. I will run super lean, like 10 percent lean on fuel trims.

[GHuggins]

I am using the fuel trim percents.. Off of a guide I've followed on here. DFCO, COT, LTFT's and MAF off. Staying out of PE. My table axis's are the same for the VVE table. I may try to re install HP tuners. I get the fuel trims close to where I'd start going by halves at +-5. When I update the table, it just throws my fuel trims completely off. I will run super lean, like 10 percent lean on fuel trims.

I was referring to the actual math equation your using or are you using the one built into the scanner? I also thought you were getting "-" numbers when you hit calculate coefficients? Your math parameter is most likely just wrong and adding everything together to turn a 5 % error into a 10 or bigger percent correction... You also need to keep rich after flash in mind before logging correction information...

[imgarten.fredrick]

I was referring to the actual math equation your using or are you using the one built into the scanner? I also thought you were getting "-" numbers when you hit calculate coefficients? Your math parameter is most likely just wrong and adding everything together to turn a 5 % error into a 10 or bigger percent correction... You also need to keep rich after flash in mind before logging correction information...

I am using the one built into the scanner. I am pretty new at tuning. And yes, I am getting negative numbers in the VVE table in one zone. How do I go about getting the correct parameter? And I have edited the VVe table a couple times and got the trims to a reasonable place. They were all very negative, now they are in that -+5 range. Some just a little out of that. Now that I am trying to get my fuel trims dialed in to near zero, the trims change drastically. They go from all the cells being negative or a couple over 0 to being 10+... I don't understand why I can change the table a couple of times and then all of a sudden hit a brick wall

[GHuggins]

Once under 5% error - always use %half for corrections...

[imgarten.fredrick]

Have you seen this video?
https://www.hpacademy.com/blog/rich-...oblem-and-fix/

[imgarten.fredrick]

Once under 5% error - always use %half for corrections...

I have been trying to, and that is when the trims all shoot to positive.... This is why I am so confused

[tbrtuning]

Thanks for sharing this. I'm definitely going to look into it more

[imgarten.fredrick]

Thanks for sharing this. I'm definitely going to look into it more

They didn't say you had to re enable it in the video, but I would after you get done tuning

[GHuggins]

Have you seen this video?
https://www.hpacademy.com/blog/rich-...oblem-and-fix/

Your kidding right You can partially get away with zeroing it out, but it will cause problems on it's own which may even be why your seeing the weird after flash +10's or so that your seeing - you have to dial in the injector tip temp table for things to be correct... Here's a picture of ID1300's injector tip temp offset settings - HPT or rather the manufacturers coding only allows as precise of adjustments as .0078ms which is enough to make some difference - it needs to be finer tuned than this, but just isn't possible... Tried to load an idle log demonstrating fueling after the injector tip temp is dialed in after a hot reflash, but it was too big to load - fueling stayed right around (-3%) the entire time after a hot restart with a rare slight jump higher than that - like I said really requires a more precise adjustment than .0078ms...

[tbrtuning]

Cool. So are you using data as the injector temp rises to tune this?

Is it helpful on stock injectors also? I was wondering how zeroing this would not cause issues but was hopeful and wanting to experiment with it some.

[imgarten.fredrick]

Your kidding right You can partially get away with zeroing it out, but it will cause problems on it's own which may even be why your seeing the weird after flash +10's or so that your seeing - you have to dial in the injector tip temp table for things to be correct... Here's a picture of ID1300's injector tip temp offset settings - HPT or rather the manufacturers coding only allows as precise of adjustments as .0078ms which is enough to make some difference - it needs to be finer tuned than this, but just isn't possible... Tried to load an idle log demonstrating fueling after the injector tip temp is dialed in after a hot reflash, but it was too big to load - fueling stayed right around (-3%) the entire time after a hot restart with a rare slight jump higher than that - like I said really requires a more precise adjustment than .0078ms...

I haven't done what the video entices you to do. I just drive around for a bit then start logging. Have a link to a good start on VVE tuning? I don't know why the maths would all of a sudden just change and ruin the table. It seems like when I calculate coefficients, it changes the table drastically

[GHuggins]

Scott "Jslic" helped and taught me on this which is why I'm not posting his formulas for it... It requires a very long and drawn out process to get it right, but perfect fueling with every throttle stomp no matter the injector tip temp is worth it... Stock injectors will benefit - all injectors benefit from this...

I just don't like other people out there taking credit or making videos on Scott's work and especially going into a long drawn out description when they don't understand the table fully themselves This single table is probably the most important fueling table in the tune besides the main injector tables...

[GHuggins]

I haven't done what the video entices you to do. I just drive around for a bit then start logging. Have a link to a good start on VVE tuning? I don't know why the maths would all of a sudden just change and ruin the table. It seems like when I calculate coefficients, it changes the table drastically

It takes roughly 15 minutes for rich after flash to clear out and then you might want to do a wot pull really quickly before starting to log - this is probably why you've been fighting yourself... You can also kill long terms and make corrections off of st's only for more precise fine tuning...

[imgarten.fredrick]

It takes roughly 15 minutes for rich after flash to clear out and then you might want to do a wot pull really quickly before starting to log - this is probably why you've been fighting yourself... You can also kill long terms and make corrections off of st's only for more precise fine tuning...

I have been tuning on stft's. I hadn't tried the WOT pulls. Weather has been bad up here in Missouri. I will try that and see if that changes it.

What is odd, even after a reflash, if I put a good VVE table tune on it, log right on start up and drive 30 minutes, the fuel trims are the same... I have an E38 controller.

[schpenxel]

In the original log fuel trims really don't look that bad to me? It's def. off some at higher MAP & RPM's but it's better than most people post.

I mean.. literally up until 2600 RPM's or so fuel trims are averaging almost zero. I wouldn't even mess with anything that isn't a problem

With VVE it will never be perfect. It's trying to best fit coefficients of crazy looking equations to fit the VE table you're asking for. It can't do that perfectly, so that's why it's changing areas you aren't wanting it to change. It's trying to best fit the new data as best it can but in order to do that is having to change other stuff. Fuel trims can do their job and keep fueling "right" regardless, in part throttle areas. Once in PE, that's where I'd spend some time on. For that you need a wideband.

I wouldn't even touch anything under 2800 RPM's and you don't have a lot of data in the higher RPM's areas that are showing a lot of negative fuel trim values anyways, so not sure I'd mess with anything there either without more data. At some point you're going to have to use a wideband, you can't use fuel trims once in PE.
VVE.JPG

If I set it to only show cells where you have 50 hits or more then you get this... almost nothing more than 3% off. You aren't going to do any better than that. The few that are higher/lower than that are probably data during decel and stuff like that that I really should be filtering out but I'm not

VVW 2.JPG

[imgarten.fredrick]

In the original log fuel trims really don't look that bad to me? It's def. off some at higher MAP & RPM's but it's better than most people post.

I mean.. literally up until 2600 RPM's or so fuel trims are averaging almost zero. I wouldn't even mess with anything that isn't a problem

With VVE it will never be perfect. It's trying to best fit coefficients of crazy looking equations to fit the VE table you're asking for. It can't do that perfectly, so that's why it's changing areas you aren't wanting it to change. It's trying to best fit the new data as best it can but in order to do that is having to change other stuff. Fuel trims can do their job and keep fueling "right" regardless, in part throttle areas. Once in PE, that's where I'd spend some time on. For that you need a wideband.

I wouldn't even touch anything under 2800 RPM's and you don't have a lot of data in the higher RPM's areas that are showing a lot of negative fuel trim values anyways, so not sure I'd mess with anything there either without more data. At some point you're going to have to use a wideband, you can't use fuel trims once in PE.
VVE.JPG

If I set it to only show cells where you have 50 hits or more then you get this... almost nothing more than 3% off. You aren't going to do any better than that. The few that are higher/lower than that are probably data during decel and stuff like that that I really should be filtering out but I'm not

VVW 2.JPG

Okay I'll keep it on that tune. I'm just confused on why when I get so close it throws everything into the positives. I can post the log for you to see.


I was looking at widebands but I was unsure of which is best for the value. I want a good one and I'm willing to spend money on one. I just don't need something super amazing that another one will do that's cheaper.

[schpenxel]

Are you waiting 10-15 mins after flashing before logging? If the injector tip temp table isn't right then fueling will be a bit screwy for a bit after fresh flashes. It's pretty annoying.

Wideband wise I've had good luck out of AEM 30-0333 as long as it's a vehicle with a CAN bus (which I think any 2008+ is). I also used a PLX for about a year without any issues but it was slower. Summit has that AEM for $220'ish if I remember right

The AEM one plugs into the OBD port then HPT plugs into it and gets the wideband data that way. You don't have to run any wires to the analog inputs on the HPTuners interface and setup is really easy which makes it nice.

[sevinn]

Scott "Jslic" helped and taught me on this which is why I'm not posting his formulas for it... It requires a very long and drawn out process to get it right, but perfect fueling with every throttle stomp no matter the injector tip temp is worth it... Stock injectors will benefit - all injectors benefit from this...

I just don't like other people out there taking credit or making videos on Scott's work and especially going into a long drawn out description when they don't understand the table fully themselves This single table is probably the most important fueling table in the tune besides the main injector tables...

Agreed.

OP, you need to read pretty much the entirety of this thread. Zeroing out the table works for some but for others it needs to be worked on. Alot of trial and error went into this table even existing.

http://www.hptuners.com/forum/showth...h-after-Flash/