88t2romad

Im having a slight issue with me car. Right when i first start it up.....doesn't matter if its hot or if its the first startup of the day. It will stumble for about a minute, during that period it is extremely hard to get to rev, almost dies it i touch the pedal. I'm just wondering if there is some sort of programmed "initial startup" map that I don't know about. Or does anyone else have ideas or possible know what the problem could be?

Thanks guys.

LT-10s/S4 turbo 2

Oh, i forgot to add, after the stumbling period is over it drives just fine.

And this current "tune" is from me, im not very experienced, boost cut is also at 0psi.

rx72c

iTrader: (8)

Firstly. Move the boost cut to 07psi.(having at 00psi will give you a few drivability problems).

Next.

go to opt_mixtrim and add 15% and see if it fixes your problem or makes it worse.

if its fixes your problem, your map is too lean.
and you need to adjust your opt_aftste add around 5%

if it makes it worse.

then go to opt_mixtrm and take away -10% and see if it helps.
if it does.
go to opt_aftste and -5%

88t2romad

I woud, but i dont want to pop my motor before it gets officially tuned(ive never tuned a car before). Driveability is not that bad, i just have to be easy on the pedal.
Thanks for the rest of the ideas, ill go work on it in a little bit!

Funkspectrum

iTrader: (5)

how did this work out? I'm having a similar problem with my LT8 on an S4 TII. Mine floods out though. Once I get it to start, it runs fine....

Don't mean to threadjack

my opt_mixtrim is at 0% and I'm not quite sure what to adjust...

88t2romad

Cant say ive messed with it yet, lol. Elliot arrives in a couple hours so ill let him deal with it.

Funkspectrum

iTrader: (5)

well let me know how it turns out. I just made a few adjustments myself and I turned the opt_mix trim back to zero again.....seems ok now. I think my issue may just be spark plugs/wires...

I'm using stocker plugs with 8.5mm MSD wires but I think i'm going to switch back to the stock style wires. I think the larger wires have a harder time delivering spark with stock coils on startup....

rx72c

iTrader: (8)

putting the boost cut that high aint gona kill your engine because you control that with your foot.

anyways.

to adjust the mix trim feature.

Go to the opt_mixtrm feature, then press the RED mode button once. make the adjustment. Then press the RED mode button again. and try it.

88t2romad

Funk:

On a side note...

The mixtrim feature makes adjustments to the whole fuel curve..

If you go to Af_StE (screen 30) this function says "After start enrichment supplies additional fuel for a short period of time after starting the engine to assist with initial engine warm-up and to prevent leaning out as engine conditions normalize."

rx72c

iTrader: (8)

yes it does make adjustments to the whole fuel curve. lots of tuners use it to find out if the problem is lean or rich. then pursue the problem further.