Need help with sd tune
Need help with sd tune Tried to tune my car via speed density. Well i did a search and found all the tables i needed to adjust to start off with. I did that and flashed it and unplugged the maf. I took the car up the road and it just falls on its face and dies. I cant even make it out of the driveway. I have the ve table tuned for the maf plugged up, is there ne changes i need to make to it before trying speed density? Thanks
I had to let mine sit for like a minute before it would even idle, then it drove alright. Your ve table could just be real far off in the lower rpms. You might wanna do the 60, 80, 90% thing to get it to run enough to get some logs.
Most likely your ve table is just so far off with the addition of your cam that it doesn't like the fueling it's getting. Try scaling the first three columns of the ve and try again. My car would want to die when coming back to idle when i started my ve tune. It's much better now.
I just started my SD the other day and have no issues with idle. I put my VE table back to stock, open loop only, disabled PE, and turned off the SES lights for the MAF. I did not turn the codes off completely.
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The only real reason I would use open loop while doing sd tuning is so I could shoot for an air/fuel ratio other than 14.7, and only if using a wideband. That would come in handy to tune the ve table at high rpm, high MAP cells.
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Verdad Gallardo The one main reason I am using open loop is because I am tried of dealing with these O2's and all the problems I have had. I am going to get mine dialed in for about 14.5 during cruise and then adjust the PE table for WOT.
Also, I wouldn't feel comfortable running open loop if I didn't have a wideband. I love mine. I feel much more comfortable being able to monitor my A/F ratio at all times.
Also, I wouldn't feel comfortable running open loop if I didn't have a wideband. I love mine. I feel much more comfortable being able to monitor my A/F ratio at all times.
Yes i did disable code 102. Do i need to just check "no mil light"? I will try this tonight. I have the ve table tuned fairly decent for the cam with the maf, so do i need to go back to my stock ve and scale the first three columns for speed density? Thanks for all the help.
I changed code 102 and went back to my stock ve table. Car will actually stay running. But now i cant scan my fuel trims. What do i need to do? Im scanning dynamic airflow and dynamic cylinder air is there nething else i need to scan for my fuel trims? Thanks
Originally Posted by luvmy01ss
I changed code 102 and went back to my stock ve table. Car will actually stay running. But now i cant scan my fuel trims. What do i need to do? Im scanning dynamic airflow and dynamic cylinder air is there nething else i need to scan for my fuel trims? Thanks
Originally Posted by luvmy01ss
So if i dont have a wideband i need to tune speed density by using my fuel trims?Thanks
You can also bypass the whole trims angle and use O2 voltage
directly by forcing the car into open loop. Without the closed
loop trying to dither mixture around the O2s will tell you rich or
lean and, if you're close, even a little about how much. If you
put the closed loop enable temp high, and lock out the PE mode
(like TPS%=100) you can drive around and pull the O2 voltage
histogram, increase VE by 1 point if it's below 0.3 and decrease
if it's above 0.7 and leave alone if between the two. Take a
few passes to get right, that way, might want to do something
like <0.2 +3, <0.3 +1, >0.7 -1, >0.8 -3 etc. This will not be so
easy to do when you are at the higher MAP levels but MAP is not
really a big player, if you can get low to mid-MAP right and just
follor the usual MAP-wise profile that will be really close.
I wrote a "debug tune" for a guy that made the changes I
described, and had him run logging pulls with it. A couple of
turns through the updating drill and I got to a very different
looking, but much better driving, VE table. Have a look:
directly by forcing the car into open loop. Without the closed
loop trying to dither mixture around the O2s will tell you rich or
lean and, if you're close, even a little about how much. If you
put the closed loop enable temp high, and lock out the PE mode
(like TPS%=100) you can drive around and pull the O2 voltage
histogram, increase VE by 1 point if it's below 0.3 and decrease
if it's above 0.7 and leave alone if between the two. Take a
few passes to get right, that way, might want to do something
like <0.2 +3, <0.3 +1, >0.7 -1, >0.8 -3 etc. This will not be so
easy to do when you are at the higher MAP levels but MAP is not
really a big player, if you can get low to mid-MAP right and just
follor the usual MAP-wise profile that will be really close.
I wrote a "debug tune" for a guy that made the changes I
described, and had him run logging pulls with it. A couple of
turns through the updating drill and I got to a very different
looking, but much better driving, VE table. Have a look:
Yes, that's the way I went about it. Other guys are
using closed loop and STFT averages, I'm not sure if
there's any practical difference to it, maybe you avoid
having to apply a funky debug tune to get the data.
Ummm... I'm not the king of anything (but at least
nobody thinks I'm a queen). Just captain of my own
ship, a compass that often works and a couple of
tales to tell.
using closed loop and STFT averages, I'm not sure if
there's any practical difference to it, maybe you avoid
having to apply a funky debug tune to get the data.
Ummm... I'm not the king of anything (but at least
nobody thinks I'm a queen). Just captain of my own
ship, a compass that often works and a couple of
tales to tell.
Last edited by jimmyblue; Nov 4, 2004 at 09:14 AM.
