purevision01

The vacuum is measured in inches... discovered when mercury was put in a tube at room temp and placed under a vacuum, the mercury would rise and measured. Anyway thought id throw that out there so I can understand.... First time reading the post I was like, how can you make any boost with you foot off the gas... lol But yours sound pretty good, about what I would have them set at.

Ace83

iTrader: (6)

lol the psi thing confused me a lil too but yeah, your off throttle afrs sound like what the rest said

paul_dezod

Do you not have decel fuel cut engaged or are you speaking about high idle on a cold start?

enjoithis

"decel fuel cut" thats what its called! From my knowledge this means when decel .. no fuel?

paul_dezod

This means when your cruising or on any throttle at all (usually above 3% or 5%), and release the throttle and just coast either in gear or neutral, the AFRs will jump to off the charts lean to get better fuel economy.

Ace83

iTrader: (6)

oh yeah i forgot to check on that setting.. but im pretty sure its my fuel map.. but no im not referring to idle or start up just on decelerating after letting off throttle

purevision01

Thats correct but the injectors should open back up around 1000 -1300 rpm to prevent the engine from stalling. U kno the all so familiar buck the car likes to do when you try to come to a complete stop while still in gear.

I believe the factory leaves the injectors functioning for maybe a second or so after the gas is depressed to keep the rpms up in between shifts, but I believe the throttle plate may also be slightly ajar at the same time but never took the time out to check exactly whats causes this.

At what engine load percentage and rpm are you seeing the engine stumble?

paul_dezod

Decel fuel cut, which usually occurs anywhere from 2-3 seconds after throttle being released.

B_Real45

That's what my Unichip map does.. as soon as I let off throttle it goes extremely lean - then back to stoich. It runs very smoothly.

paul_dezod

Uni-chip does nothing. It's programmed into the stock PCM for better fuel economy.

Ace83

iTrader: (6)

my decel cut is on, now its time to play with fuel map and enleanment coefficient.. i did notice it going smoother as i leaned it out

B_Real45

What does that mean? It does nothing to the stock ECU. It alters signals coming out of the ECU as opposed to Greddy or AEM that intercepts the signals before the ECU.

purevision01

I believe paul is talkin about the decel fuel cut.

Ace83

iTrader: (6)

I guess what paul meant is that its our stock ecu tune that control that and not the tune that came with the unichip.. the nice thing about the piggybacks is that it allows you to retain some tune/settings that are designed for drivability and are reliable from the factory instead of figuring out to make a complete tune.

paul_dezod

Yes Ace, I was referring to it doing nothing with respect to DFCO. I like playing with it. You can make it as aggressive as you want, a laxed way or not on at all. They joys of a standalone are second to none.