Need help w/ base tune.
These new injectors (160's) I initially used that spread sheet to do them. I think they were like 190 at the top of that chart. when I entered in my fuel pressure (42psi....i did lower it from 50psi) the end of the chart i believe was at like 190# I also tried setting the rate at a flat 160 across the chart, then lowered it to 155 because of the lowered fuel pressure.
What I dont understand is that it fires right up fine. Idles fine for 10-20 seconds, AFR's read 10.9:1 for the first few seconds, then moves to about 14.5: for the remaining while idling perfect. then after the 20 seconds it starts surging going from 9:1 to 16:1 super rich to lean.... and moves so fast and the squares in the histogram change also fast. The VE table isnt that rough where they'd do that.....ive tried other VE tables also.
I have no clue what tables its doing this off of. Somewhere i think there is a table i have messed up. The idle air flow ive deviated 10 numbers each way.... no results. VE table.... tried several... adding, subtracting... no results.
Is there a writeup somewhere that tells you what table it reads off of in the sequence it runs?? Like this....
1. Start up - cranking AFR table (obvious)
2. After start - after start table (obvious...with the decay and delay)
3. .......then wherever it goes from there for how long??????????????????
Last edited by pwrtrip75; May 26, 2011 at 11:01 AM.
You want your idle cells and the ones around it to be at the same timing value. I have mine at 29. It smoothly ramps out to the other values where it drives. It comes into and goes out of idle smoothly. It always looks for 29 at and around idle. Dead smooth.
I set closed loop enable etc. to 284 degrees. I think I see what it was doing now.. (I think). I know my VE table is wacked and I did work on the idle/low RPM cells but couldnt figure out why it was moving... If it was in closed loop that explains it... at least what im understanding of how it works.
Thanks.
From idle to 2000rpms and about 30kpa to 80 it is 14.5:1 AFR.
Anyone know what this could be?
Also....have you picked up a copy of this? http://www.thetuningbook.com/
Very helpful, and will take much of the mystery out of tuning your car. Just a thought.
Last edited by salemetro; May 27, 2011 at 04:42 PM.
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Also....have you picked up a copy of this? http://www.thetuningbook.com/
Very helpful, and will take much of the mystery out of tuning your car. Just a thought.
The book has been on back order for several months... Ive emailed them probably once every 2-3 weeks for awhile now. Know of one for sale somewhere?
OK....This is probably WAY off-base....but are you sure that you're not having issues with your fuel pressure regulator? Just a thought.
I spent quite a bit of time last night dialing in the VE table at idle and up to like 15% neutral revving. IF it can get started it idles good now.
The first 4-5 seconds it starts it is pig rich and idles at 400rpms. then if it dont die it will go up to about 1000 like it should and actually idle.
One problem i think i had was an afterstart enrichment table.. multiplied fuel per ETC. So the warmer it got each time i made a change and started it would be all screwed up... I must have added to the VE table 10 times and made no difference because as the temp went up this table kept leaning it out.
I cant get it to operating temp cause it would only run for so long. after finding this table and flat-lining most of it the AFR's dropped down to usable and the thing idled like a dream. Talk a bout a fight... thats why they need to have a writeup of the sequence this whole operating system works in and what tables will affect what and when.
Edit* now its cooled off its fires instantly and runs again.... but starts out really rich and low idle. ????????? Pretty lost here.
Last edited by pwrtrip75; May 28, 2011 at 06:18 PM.

I should figure out what its supposed to read for E85.... I was under the impression that even though stoich is 9.7 it would still read 14.7 on the WB???? Im not fully understanding the difference between gasoline and E85 tuning wise. Previously all I had done is tuned vehicles with gasoline...then changed the stoich value for E85 and that was it... and it worked. Now starting fresh w/ E85... i think i need to do some reading.
I should figure out what its supposed to read for E85.... I was under the impression that even though stoich is 9.7 it would still read 14.7 on the WB???? Im not fully understanding the difference between gasoline and E85 tuning wise. Previously all I had done is tuned vehicles with gasoline...then changed the stoich value for E85 and that was it... and it worked. Now starting fresh w/ E85... i think i need to do some reading.






