zacht

iTrader: (18)

UPDATED WITH TUNE FILES AND LOGS BELOW!!!!!!!!1


hey all. i have hptuners and all, but im not an expert tuner by any means. i recently dropped the k-member for a h/c install. ill list my setup.

fast 92/95mm tb, ported (ran before h/c)
tsp stage 1 243's
pat g cam 231/239 .617/.623 114+4
melling pump
katech chain
7.4 pr
1 3/4 headers/ory/ slp lm1
42lb green tops
255 with hotwire
stock maf...i know..

midwest chassis 9in 3.89's

6 speed car just installed monster stage 3

also have nitro daves wet kit

i had it tuned before and it ran great. i found a ve table from a car on hptuners tune repository running 42lb injectors and a 233/239 tsp cam (it'll be close...)

i have the 42lb tables setup off a injector disk that has all the different injectors scaling.

i have everything setup. when i have the maf plugged in my wb goes to 16:1... and i hear (and see) my iac valve open all the way up...310!!!! crap. and my idle drops to about 550rpm..

when i unplug the maf it goes to 14.7 and starts to idle around 900-1000...i tried driving it this way and it bucks and surges pretty hard...hard to roll on the gas.

guess im wondering if i should post up some tune files and logs to anyone so someone can point me in the right direction...

thanks guys

bayer-z28

iTrader: (14)

I'm not an expert either (at all; still a newb).... But check to see if the MAF fields weren't disabled. If it WAS disabled though, it shouldn't make a difference if you plugged it in. Go back through and check the MAF HI and LOW Delta and see if they're not set to Zero. (Zero = disabled). Maybe someone was kicking around on an open loop tune and forgot to return those fields. Also the HI and LOW TPS Delta.

And when the MAF and injector settings are dialed in correctly, you'd prolly need to go back to open loop and re-write the VE table. (Thinking out loud here) It'd almost be easier to do all that than have to deal with the headache of someone else's VE tables screwing you up.

zacht

iTrader: (18)

true! ill check that out! thanks man!

see i was wondering...i think the stock ve table starts around 41...and ramps up to possibly 97...

the one i got from the repository starts at 27 and goes to 110...

bayer-z28

iTrader: (14)

^ It all depends. Your exact mods on my car will not yield the same VE numbers, but they MAY have a generalization.

GO BABY GO

iTrader: (15)

Someone elses tune may sound like a good starting point but there are too many variables to make it worthwhile to me. What i like to do is tune the Ve table first, the maf table next, and then timing. Once you get them all lined up the IAC counts may come down but if not you may have to adjust the tb screw and do the reset procedure.

The thing that made the night and day difference in my car was changing the stoich ratio for e10 because thats all that is available to me.

For a cam of that size i would guess that there is always going to be some bucking or surging down low but

Did you reduce your ve table in the low rpms alot? Your probably going to want more timing down low around idle. Mine idles like a champ with 28 degrees of timing.

Nothing wrong with the stock MAF. It supports quite a bit of power just fine.

Your wideband may not be your friend in the idle area. Just because it reads 16:1 doesnt actually mean you are too lean. The engine may be getting too much fuel down there to burn up and making it show false lean.

As long as your injector data is right, these are just some things to think about. They all make a difference.

zacht

iTrader: (18)

yeah ive been kicking that idea around. bumping the timing down low. it idles right now at 22 degrees timing...well not well. still really lean tho. guess i dont know why my afr goes to 14.6 when i unplug the maf...

and my ltft are at 25% off the bat!!! and when my o2's start switching the stft's just start going right up to 25% too...

ill bump the timing up...then look into the ve tuning...then maf... beings its super lean tho, wouldnt that mean i need to lower my values down low on the ve??? correct? i think down low on my ve its around 27...and upon reading tuning information they say whatever your ltft's are subtract that value from your ve....wtf??? idk...ill look at it.. ill get on my other computer tomorrw and show some logs....crap...

im about to jerk out the 42s and throw in the 28.8s again...i got to break in this clutch as well...not to mention kool deadwood nights next weekend...

GO BABY GO

iTrader: (15)

Well I think you would be better making an error histogram and going for a cruise on the highway. Then take your data and "multiply by % - half" into your ve table. For tuning, I turn off fuel trims and hit the reset button every time before i start logging so they don't mess with my results.

My car idled very poorly with timing that low.

Tuning is extremely frustrating but hang in there.

zacht

iTrader: (18)

I hear that! Yeah im just scared to drive it as is. Ill get it. Yes tho. Tons of patience!

SSpdDmon

iTrader: (10)

Some timing hints:

27~28* should be enough for idle assuming it's an M6 car (or an A4 car in Park/Neutral). It may need a little more if it's an A4 in Drive.

On light throttle application under 2K RPM, pay close attention to your grams/cylinder readings. This will show you what timing cells are referenced in the hi/low timing tables. For this range, lower timing works wonders. I think most of my low throttle, low RPM cells are around 22*. Basically, I'd suggest looking at an '02 tune file in this region and expanding upon the dip in timing they have in this region.

Results for me were:
http://www.youtube.com/watch?v=U2MnX_ykLeo

As for AFR, significant overlap in your cam's design is going to push unburnt oxygen into your exhaust - more so at lower RPMs. If you're idling at 14.7:1, it's definitely running too rich. I think mine idles around 17.5:1 on the WBO2...and it does so just fine. Once I get up over 2k, fueling smooths out in the 14.7:1 range. Don't let the numbers fool you.

That's the reason I decided a while back to go MAF only. I don't have the right equipment (using only a WBO2) to know if fueling at lower RPM's is right. So, trying to put a VE together is like a new way of playing of pin the tail on the donkey...and I don't want to do that with my car. Running a stock MAF curve, you at least have a damn good guess at where the AFR should be assuming your IFR is linear and accurate in the lower MANVAC/higher RPM regions.

zacht

iTrader: (18)

Ok! Im taking all this advice well and going to put it to good use tonight. Just weird still that its at 16 afr and my iac counts jump up to 310...my afr gauge is a ngk afx only goes to 16...I need to get those down also. Ill mess with it...

SSpdDmon

iTrader: (10)

You're guage only shows 16:1 because that's the limit of it's operating range. It could be 19:1...but the display will still show 16. The problem you experienced could be an excessive lean condition with the MAF enabled - so much to the point that the car was struggling to maintain an idle. So, the PCM adds throttle via the IAC and dumps in fuel via the fuel trims to try and restore some sanity to the idle. That is happening either because your tune is THAT far off with the MAF enabled OR you have a bad MAF. I'd lean towards the first possibility way before the second...but I wouldn't rule it out.

zacht

iTrader: (18)

true! i know my gauge tops out at 16:1...but i went and drove it...only to aobut 2500rpm (clutch break in...) but my gauge was working and my arf started dropping to 12.5:1...so i know thats probably a little rich...but at least i know im close....

my iac counts right now are at 71...which is respectable, i upped the timing lower rpms. it ran and drove ok...some dead spots here and there, but ok. my ltft's are ar 25% and stft's are up to 50%....but....my 02's aren't swithching which says im in open loop still...gay. but i know the car's close.

i set the idle with tb screw and tps reset...and timing added...

but at least i know im getting close.

im going to re-set ltft and stft....

just sucks im also working on a 52 f100...5.3 swap at the same time...lol took a little time tonight...

edcmat-l1

iTrader: (10)

That's not right. If your fuel trims are active, you're in closed loop. The O2s not switching is a problem with your O2s, not that it's in open loop. If it were in open loop, you fuel trims would not be active. To be more specific, your long terms can be locked in at a certain value, and it be in open loop, but if your short terms are not moving, it's open loop. If they are moving, closed loop.

The fact that the O2s are not moving, is probably the reason why it's going so far out of whack on the fuel trims. Get the O2s fixed first, or set it up in open loop, so it won't do what it's doing.

It would help greatly in you posted a tune and a data log.

zacht

iTrader: (18)

ok! my fuel trims aren't moving at all.... and neither are my 02's.

ill get one posted tonight!

02's shouldnt be shot...they have like 5k miles on them. i have a new set tho too...exra...

zacht

iTrader: (18)

got some tunes and logs for people to check...dont laugh too hard either...

i need some help soon!!!