Car starts then instantly dies using ceddys SD rom.

[chronicvex]

On my MAF tune everything runs perfectly except when I do a warm start it cranks fine then drops in RPM like its going to die but comes back to life and idles perfectly. When I use SD rom on a cold start my car will die instantly even if I'm flooring it. How do i adjust start up fuel using Ecuflash?
Thanks

 

[GSXDNA]

On my MAF tune everything runs perfectly except when I do a warm start it cranks fine then drops in RPM like its going to die but comes back to life and idles perfectly. When I use SD rom on a cold start my car will die instantly even if I'm flooring it. How do i adjust start up fuel using Ecuflash?
Thanks

Does your SD start ok on a warm start? Are you running pump or e85?

 

[chronicvex]

No its even worse on warm start. I only run pump gas.

 

[MY1GDSM]

Do you already have a VE map built? I know I remember telling you this before... that regardless just becasue they are SD ROMS doesn't meen they are going to start the car for you with out being setup Properly first.

So.... .Are you flashing the ROM with All the proper settings for SD...

 

[H@xtGSX]

I am in the process of setting up my SD with 1.9vCSD also. Just getting started though. The VE table Ceddy has included is a ballpark table... I am lucky enough that it's ballpark enough to run decently, but not great. I will be watching this thread though. I know there's a lot I don't know about this SD with CeddyMods. I've muddled through a lot of threads on it, but since you have experience, what are the basic mandatory settings and table builds? I know the VE table should match the MAF calcs, and the rest is stuff I am trying to figure as I go... My idle is not so hot if it is switched to SD too, but it doesn't die immediately.

 

[chronicvex]

http://img40.imageshack.us/img40/5676/sdlog.jpg

Theres an example of the VE maps I'm using. Of course I filled it in a little more with other logs.

I have tried multiple combinations of setup bits for the SD rom. Can you tell me what I should have enabled for building my VE tables and then what I should have enabled for when I'm running full SD?

HaxtGSX- What setup bits do you have enabled when you get it started? Is that with MAF still plugged in? Thanks
Thank you!
P.S I still am gonna need you to tune my car my1g! I had to drop all my money into a new trans because it got really bad so it could be a couple weeks.

 

[H@xtGSX]

Speed Density « ceddy.us

That is of course the manual Ceddy set up for it, and should explain everything... I am working through it slowly, as I have discovered that it's not forgiving in the least if you change anything "just to see what it does". I did this... just made a mess.

I haven't switched to full SD. To do that, you'll be wiring the IAT in place. Once that is done, you no longer have the MAF signal, so the SD VE Table is the only thing controlling the engine. My MAF is still in right now. I just have a couple bullet connectors on it right now, so I can check with the IAT... I'm thinking the VE table needs to be adjusted for the mid-range of the normal conditions. I have tried to do it with the Baro locked and unlocked, just to see the difference. There's some change, of course, so in certain conditions the driveability is going to change some. The IAT with the VE is the compensation, but it lacks the baro compensation, which I think smooths the MAF signal much more than people may think. I am just speculating about this though... I have no proof.

 

[chronicvex]

I have brushed through that page with a fine comb. I still have questions like - Am I supposed to be building my VE table using the MAF rom since my SD rom wont even let my car run? Do I have ADC 10 bit Map enabled for building my VE table with MAF still hooked up? For a 3 bar Map sensor I leave the SD calibration values as is correct?
I'm just trying to find out any little thing that is messing this up for me.

 

[H@xtGSX]

Yes, I was setting up the VE Table with the MAF rom. It won't run worth a crap until the VE table is at least close. Yes to the ADC 10 bit also. I never messed with it, as I have a 3 bar sensor. If you're using something else, you'll need to edit that like described.

You run it on your BEST MAF tune FIRST. That's where you'll log for the VE table in the SD rom. Then edit the SD rom to correlate. Once you think your close, you can flash it over and test it. The final test is the IAT switch over... if it's close, it'll run.

 

[chronicvex]

Ok, I'm going to give it another go with logging VE since I changed some stuff up recently. Nice to know I was doing it the right way though. Before it was a shot in the dark. Thanks man!

 

[H@xtGSX]

That's the thing that I think a lot of people don't quite get until AFTER they start messing with this... you have to get a really dead on, GREAT tune on the standard MAF rom before even thinking about the SD swap. I didn't realize this initially until my VE table basically told me "YOU SUCK. DO IT RIGHT." If you log the MAF stuff on a crappy MAF rom tune, you'll get crappy VE tables, and it'll run like.........crap.

The SD switch over is only to be tried once you think you've got it absolutely dialed in normally.

 

[chronicvex]

Yea, I recently improved my MAF tune significantly. The only thing I haven't messed with is timing, but hopefully that wont e'ffect me being able to get my car running on SD. Once I have the money to get my MAF tune done by my1g I will be redoing my VE tables again.

One more question for you. When you were logging for VE tables did you leave the VE table under MAF rom at 100s or did you copy over the default VE table from SD rom to be included in the formula?

 

[H@xtGSX]

Left it alone. You're after the log info to build the SD rom, not the MAF one. No point in messing with the VE table on the MAF tune.

 

[chronicvex]

What I meant was copy them over not for use in the MAF table, but so they're included in the SD VE % formula that evoscan creates as it logs. On one of my other threads someone said you want to use ceddys default value in the formula.

Log the MAF airflow counts vs. SD airflow counts. The values that goes in the VE table should then be approx:

New VE = Old VE * (MAF-SD)/SD + Old VE

Ex.
MAF: 150 counts
SD: 68 counts
VE: 100 %

New VE = 100 * (150-68)/68 + 100 = 221


Since you can log all these parameters, you can actually set up a loggable parameter that automatically calculates this for you. Then you can pull it up in the Map Tracer in EvoScan.




Also beware that you may have to add a little fuel through the startup enrichment table if your car struggles on cold starts.

 

[MY1GDSM]

Maybe it's me... .

But, I always see people trying to use "auto" adjust features or logging values to try to build SD maps when in reality after the amount of time people try to figure out this stuff...

They could have just treated the SD map like a Injector pulse width map and adjusted adding fuel or taking it away at the points for each cell. to get things lined up.

To many variables for a lot of this stuff to work 100% correct. an in the End to many end up blindly copying info from things like this to only have there cars run worse and not grasps what is really at hand all along.

That's just my take on it though. I've never used any of this stuff.

My formula is this

Desired target AFR / Actual AFR = percent AFR change needed. IDK I do all this in my head... But if you know what the AFR you want is THE afr your hitting along with the Rpm/load cell your in it's not that hard to just make changes and get it done.

One thing that can help is to set you Target ARF's as one ARF for everything in load to start get thing lined up since it won't be a curve it will be easier

Then when done do some real tuning by just changing your AFR map.