LETZRIDE

iTrader: (6)

Is there anyone that has tuned there VE table but have maxed the values out? I've been doing ve tuning on my car and I have pretty much maxed my AE tables, and maxed my 100 KPA VE cells and am still 12% short fuel.

My question is what could cause this to happen? The car is cam only and it does not have a nasty cam by any means...the MAF is nowhere near being maxed out either, but I cannot run a maf on my car. I'm thinking there may be a problem somewhere along the line, but I am not sure what could trigger this? A vaccum leak maybe?

But this is the thing...the Part throttle and idle values are perfect...it is within 2 % of the commanded value.

I am sure someone must of run into a similar problem before?

macca_779

You certainly haven't maxed your VE out. More likely your injectors.. Check you IFR values are correct for what you have and what's your IDC.

LETZRIDE

iTrader: (6)

I haven't been logging IDC lately, but they should not be maxed for my application...the are 36#'s which is more then enough for my given mods, and the injector scale is correct. These injectors should give me a chance to grow in mods...I don't believe my VE should be maxed out either...that why I want all possible problems that could ever cause this so I can begin taking them out one by one.

jimmyblue

iTrader: (11)

Start with how you know you're short fuel at WOT. No
instrument can be blindly trusted; even a properly working
wideband meter can be spoofed by misfires, etc (as might
come from a single cylinder lean-out or spark blowout).

Check rail pressure at WOT; big injectors won't deliver if
you have a plugged filter, kinked feed line, weak pump or
pump electrical supply. The normal stock LS1 seems to
drop from 58 to maybe 52PSI at WOT. More than this, is
reason to suspect the feed can be improved.

Frost

iTrader: (45)

Are you sure the car is actually IN SD? P0101-3... one of those must be set.

LETZRIDE

iTrader: (6)

I have a fuel pressure gauge...the thing really doesnt move more then a few hairs...I haven't figure out how to log it through hp tuners yet...I want to find out so I can see actual pressure at WOT...but to be honest I am questioning whether or not the damn thing is even accurate...

fuel filter was done about 1.5 years ago...how else could I tell if I have a weak pump or electrical supply? would the fuel pressure not drop when at WOT then?

I have the pressure being taken at the schrader valve...

I don't recall ever seeing any kinked lines while under the car...

as far as the pump goes, could it just be bad at WOT? car fires up at the first turn of the key on the first crank always.

Only thing electrical that I am concerned about and also stumped about is lately my volts gauge is reading a little closer to the midway point, and when I come to a stop she dips down to red and then back to the halfway point...but as far as I can see when driving she stays put just above half there...

LETZRIDE

iTrader: (6)

cars definetly in SD...MAF is completely unplugged, and it is throwing the code (I think it is PO104,) not 100% sure on the coding, but the light is lit, and the code is for MAF failure, and it is unplugged.

Besides that, My maf is dialed in, so if anything I wouldn't be lean at WOT lol...

LSxPwrDZ

iTrader: (4)

what are you tuning with? Can you post your tune?

LETZRIDE

iTrader: (6)

I am tuning with Hp tuners...

Here is my tune. It is the 3.8, so its a little different the what you are probably used to seeing...but honestly this is not a v6 related issue I don't believe... v6 guys can't help me as they all tune through the MAF, Im about to be running 6 throttle bodies soon so no MAF for me...gotta figure this out...

Thanks in advance guys...

SDAE adjustmentsECT.hpt

Patrick G

iTrader: (14)

Have you increased the rpm at which the MAF stops blending with the VE tables? Stock, it's 4000 rpm. You'll need to raise this to above your rev limiter or you won't see any changes at higher rpm.

LETZRIDE

iTrader: (6)

don't even have that option for us unfortunatly...

LSxPwrDZ

iTrader: (4)

Yeah there is very very vague tables in the v6 models unfortuneatly. It is really weird that the PCM isn't adding fuel from the VE. Unless there are still some hard coded problems we can't see that block dynamic airflow calculations above a certain RPM. If you can do a datalog file that shows dynamic airflow along with mass airflow (even though it's not functioning it should still report) and IDC as well as Injector Pulsewidth. Maybe we can help lead ya in the right direction.

JonCR96Z

iTrader: (33)

Might be something in the V6 tune that your don't have access to (like secondary VE). Do you have a log of what it's doing?

The tune seems to be set up correctly for what you're doing (considering what few tables that you have).

LETZRIDE

iTrader: (6)

I'll give ya a few logs here...i dont have any dynamic airflow, I'll look to set that up...never heard of it though?

I stopped recording IDC, I have 36# injectors which is more then big enough for my mods...I think it was back at like 65-70% or something like that when I was logging it, i'll have to dig through some old logs to confirm.

I'll plug the MAF back in tomorrow to see if it can get some readings. I have it totally unplugged at the moment.

Part throttle tables are perfect, I have them within 2% after a few correction log/tunes...Just literally 5 cells in the 100kpa section won't budge and I have them maxed at 200%. Would a vacuum leak cause something like this?

Ive thought about a bad MAP sensor to, but why would I get good readings at Part throttle?

Here's a couple logs...I'll see if I can log the above mention tommorrow on my way to work.

m20.hpl

m10-1.hpl

JonCR96Z

iTrader: (33)

You say 36 lbs injectors but your have 33 in the tune, but you're real problem looks like that you have LTFTs and you don't have closed loop disabled.

You'll never hit the number if you don't clear the trims. It's always gonna keep pulling fuel. Also disable decel enleanment while tuning.

LETZRIDE

iTrader: (6)

closed loop should be disabled... its set to not come on until the coolant hits 120degrees celcius, which if it does I need a new motor...

LTFT's keep going to -25 or so, sometimes I forget to reset them, but I have noticed it really isn't making a difference...I'll reset the fuel trim and run the exact same run and the numbers will be the same pretty much.

as far as the injectors go, they are 36# injectors, but with our fuel pressure they act like 33#, a little less at WOT as well...

JonCR96Z

iTrader: (33)

If you clear the trims then they won't come back unless closed loop is active. Your STFT and LTFTs should always be at 0 while tuning. Otherwise you're pissing in the wind.

If your injectors are 33lbs on your pressure, then you have 33lb/hr injectors. Are you sure on what they are rated at? What is your fuel pressure?

Edit: yeah I see where you have CL turned off in the tune. Are those logs using that tune? Do these cars use OL STFTs? If you can't get them to go away then just unplug the O2s.

LETZRIDE

iTrader: (6)

I dunno about the CL issue then, cause even forcing it into CL with the option in the scanner yields the same results...

100% sure they are rated at 36# and 33# on our cars.

I haven't been able to log fuel pressure yet...I got a gauge but haven't figured out if/how I can log it with hp tuners...the thing barely moves a hair, so I am wondering if it is even accurate...looks to be around 55-60 psi though. I would like to log it though so I can see 100% what it is in WOT. It's a cheapy glowshift, probably shouldn't of cheaped out on it

The logs are using that tune yes, but a modified version of it...Ive been saving over the tune, but the only differences would be lower numbers in the AE multiplier tables...so part throttle is getting richer on me, and even some of the 100kpa WOT cells but not from 4800 rpm and higher... I log and adjust it, so in those scans the part throttle is a little off, but after a couple logs literally part throttle is within 2%...cruise is beautiful...my command AFR is exactly where it should be to. I'm really hoping this is something stupid...I really don't want to have to jump to a stand alone because of literally 5 cells... and I want to avoid replacing as many sensors blindly as possible...

edit: They very well might use STFT in OL. I might just pop out all the O2 sensors except for the wideband this week. I dunno if that will bring my values from 200% in the ve to around 100ish though? lol

LSxPwrDZ

iTrader: (4)

If they are rated at 36# for normal fuel pressure which is 3bar/43.5psi and you are running 55-60psi of fuel pressure then your injectors are actually acting like 41.5# injectors.

Anytime you increase the fuel pressure, it makes the injectors act bigger because the higher pressure makes them push more fluid for x amount of milliseconds. I still don't think that is your problem though because with your injectors set lower then they actually are would make the injector pulsewidth go up.

Dynamic airflow is the calculation of airflow based off of the temperature, VE and RPM. It basically turns the VE table into airflow numbers.

LETZRIDE

iTrader: (6)

They're rated at 36# for a grandprix which apparently has more fuel pressure then us.

So would the dynamic airflow be the info I have in chart number 7 on the vcm scanner? I don't see a PID for this, so what type of calculation should I use/ how can I set it up?