What advance table used on startup?
What advance table used on startup? What spark table is used on initial startup? Main Spark vs. airflow vs RPM? Or idle spark advance? Or?
The reason I ask is that when I turn the key it grabs up to about 1400 rpms, then quickly drops like it wants to die, and then catches and holds idle steady.
My log shows that as soon as I hit the key it shows 13 degrees of spark for about 5 frames, then when it catches and holds idle but spark is everywhere. Note that my Main Spark table is the only table that has values lower than 22 degrees. My idle spark advance is all at min of 22 degrees in idle area. What table does it use when cranking?
This is kind of what the log looks like:
RPMS Timing Cylinder Air
123 13 .47
137 13 .47
450 13 .43
1396 13 .23
1343 11 .15
1104 15 .21
901 22 .21
620 22 .23
423 22 .27
504 22 .30
503 22 .34
744 23.5 .35
1220 26 .34
1546 11 .32
1281 10 .25
1173 14 .23
1073 18.5 .22
1089 22 .23
1128 22 .23
1125 20 .23
Thanks!
The reason I ask is that when I turn the key it grabs up to about 1400 rpms, then quickly drops like it wants to die, and then catches and holds idle steady.
My log shows that as soon as I hit the key it shows 13 degrees of spark for about 5 frames, then when it catches and holds idle but spark is everywhere. Note that my Main Spark table is the only table that has values lower than 22 degrees. My idle spark advance is all at min of 22 degrees in idle area. What table does it use when cranking?
This is kind of what the log looks like:
RPMS Timing Cylinder Air
123 13 .47
137 13 .47
450 13 .43
1396 13 .23
1343 11 .15
1104 15 .21
901 22 .21
620 22 .23
423 22 .27
504 22 .30
503 22 .34
744 23.5 .35
1220 26 .34
1546 11 .32
1281 10 .25
1173 14 .23
1073 18.5 .22
1089 22 .23
1128 22 .23
1125 20 .23
Thanks!
TECH Addict
Joined: Jul 2002
Posts: 2,261
Likes: 0
Base spark tables.
Idle Flare Control Spark
Idle Underspeed Error Spark
Idle Overspeed Error Spark
Also look at these airflow adders on startup:
Startup Friction airflow.
Startup airflow correction.
Also, related decay and delay.
Hope this helps some.
Idle Flare Control Spark
Idle Underspeed Error Spark
Idle Overspeed Error Spark
Also look at these airflow adders on startup:
Startup Friction airflow.
Startup airflow correction.
Also, related decay and delay.
Hope this helps some.
Originally Posted by Bink
Almost forgot....crank timing while cranking.
oh oh. where is this one located exactly? And how is this table handled? Just raise it and see what happens?
Thanks
TECH Addict
Joined: Jul 2002
Posts: 2,261
Likes: 0
...under general spark tables........... which editor are you using ?
I'd leave crank spark alone.
Try reducing your Startup Airflow Correction and Startup Friction Airflow.
Your Idle Flare Control is probably chopping your Spark Adv. due to excessive air added on start up.
You might increase your Base Spark Timing also ...22 * is pretty low.
If you have EFILive you can scan the Spark DMA pids and watch the start up timing....see if the Idle flare is chopping it. I wouldn't change Idle flare Spark since it's doing what it's supposed to.
FWIW.
I'd leave crank spark alone.
Try reducing your Startup Airflow Correction and Startup Friction Airflow.
Your Idle Flare Control is probably chopping your Spark Adv. due to excessive air added on start up.
You might increase your Base Spark Timing also ...22 * is pretty low.
If you have EFILive you can scan the Spark DMA pids and watch the start up timing....see if the Idle flare is chopping it. I wouldn't change Idle flare Spark since it's doing what it's supposed to.
FWIW.
Originally Posted by Bink
...under general spark tables........... which editor are you using ?
I'd leave crank spark alone.
Try reducing your Startup Airflow Correction and Startup Friction Airflow.
Your Idle Flare Control is probably chopping your Spark Adv. due to excessive air added on start up.
You might increase your Base Spark Timing also ...22 * is pretty low.
If you have EFILive you can scan the Spark DMA pids and watch the start up timing....see if the Idle flare is chopping it. I wouldn't change Idle flare Spark since it's doing what it's supposed to.
FWIW.
I'd leave crank spark alone.
Try reducing your Startup Airflow Correction and Startup Friction Airflow.
Your Idle Flare Control is probably chopping your Spark Adv. due to excessive air added on start up.
You might increase your Base Spark Timing also ...22 * is pretty low.
If you have EFILive you can scan the Spark DMA pids and watch the start up timing....see if the Idle flare is chopping it. I wouldn't change Idle flare Spark since it's doing what it's supposed to.
FWIW.
What would you suggest for base spark? 26? 28?
Last edited by 99whitews6; May 1, 2006 at 05:12 AM.
Ok, I got the actual start figured out. I added some timing and now it jumps right to 1100 RPMS like commanded. 
Then after a couple seconds it goes nuts and surges consistently for like 2 minutes. 
Log file is attached. I can send the tune if someone would like to look at it(Too big to post here)
Then after a couple seconds it goes nuts and surges consistently for like 2 minutes. Log file is attached. I can send the tune if someone would like to look at it(Too big to post here)
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Originally Posted by Bink
How much Idle timing do you have now?
Looks like you are banging on the over and underspeed Idle Spark control?
Looks like you are banging on the over and underspeed Idle Spark control?
What EXACTLY should I do to these two tables?
Thanks BINK
Overspeed:
0.00000 -1.01099 -2.00000 -3.01099 -4.00000 -5.01099 -6.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000 -8.00000
Underspeed:
0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 4.00000 4.00000 4.00000 4.00000 3.01099 2.00000 1.01099 0.00000
Originally Posted by Russ K
Why is your B2S1 O2 sensor not switching? Are your LTFT trims enabled?
In the ect spark advance correction table, any -timing value from 185F and
colder, set it to 0.
Russ Kemp
In the ect spark advance correction table, any -timing value from 185F and
colder, set it to 0.
Russ Kemp
Really, anything lower than 185 set to zero?
I would then re-enable the LTFT. The - timing values are to heat up the cats
quicker during warm up. I actually add + advance untill the ect is 113F.
Make sure to set the multi table to 1.00. Starting at -40F I'm at 8*, then
by 113 down to 2*
Russ Kemp
quicker during warm up. I actually add + advance untill the ect is 113F.
Make sure to set the multi table to 1.00. Starting at -40F I'm at 8*, then
by 113 down to 2*
Russ Kemp
Originally Posted by Russ K
I would then re-enable the LTFT. The - timing values are to heat up the cats
quicker during warm up. I actually add + advance untill the ect is 113F.
Make sure to set the multi table to 1.00. Starting at -40F I'm at 8*, then
by 113 down to 2*
Russ Kemp
quicker during warm up. I actually add + advance untill the ect is 113F.
Make sure to set the multi table to 1.00. Starting at -40F I'm at 8*, then
by 113 down to 2*
Russ Kemp
So, I was informed that my IAC Park Position table was out of wack and I didnt have the right values in the Effective Area table(shift 6 to right). Prior to making the
changes back to IAC PARK stock values and Effective
area shifted 6 to the right, my tune was perfect other
than startups(which is why this thread started!
). There was no surging while slowing
down, when shifting from P->D or D->N->R it would move
maybe 100 RPMS.
Now that I have changed the IAC PARK back to stock and
the Effective area 6 to the right I can NOT get this
thing to idle when shifting into a gear. I logged
from cold (LTIT+STIT), shut it down, input new values
for Idle Airflow INGEAR, and started it back up.
Hunted a tad, then smoothed out nice. I let it sit
for a couple minutes and then put it in gear, RPMS
shoot down to about 350 and then surge a couple times
and then it smoothes out a little, but still hunting. I then start to coast down
the driveway and the thing dies on me. So I put it
back in park and let it idle ten minutes to learn.
Shut it down, wait two minutes, start it back up and
same thing happens.
Whats going on? Where did I go wrong?
My buddy is coming over tonight so I can show him the
car so I need it running. I decide to put the old
tune in with old incorrect IAC and Effective area values in and
the thing runs great again other than 3 minutes of
hunting on start ups! Is there someway to reset LTITs
or somthing that I am not doing right?
changes back to IAC PARK stock values and Effective
area shifted 6 to the right, my tune was perfect other
than startups(which is why this thread started!
). There was no surging while slowingdown, when shifting from P->D or D->N->R it would move
maybe 100 RPMS.
Now that I have changed the IAC PARK back to stock and
the Effective area 6 to the right I can NOT get this
thing to idle when shifting into a gear. I logged
from cold (LTIT+STIT), shut it down, input new values
for Idle Airflow INGEAR, and started it back up.
Hunted a tad, then smoothed out nice. I let it sit
for a couple minutes and then put it in gear, RPMS
shoot down to about 350 and then surge a couple times
and then it smoothes out a little, but still hunting. I then start to coast down
the driveway and the thing dies on me. So I put it
back in park and let it idle ten minutes to learn.
Shut it down, wait two minutes, start it back up and
same thing happens.
Whats going on? Where did I go wrong?
My buddy is coming over tonight so I can show him the
car so I need it running. I decide to put the old
tune in with old incorrect IAC and Effective area values in and
the thing runs great again other than 3 minutes of
hunting on start ups! Is there someway to reset LTITs
or somthing that I am not doing right?
If you're running your car in closed-loop mode, then you might not want to increase your spark at idle much past about 18* as it can increase surging when trying to run with closed-loop fueling.
When changing things around that affect idle you may want to unhook the battery each time to erase whatever idle-learn saved during unsuccessful attempts to get the idle right.
I'm not 100% positive but I don't think the learned idle values are erased during a re-flash. From what I've observed it looks like you have to unhook the battery to clear those.
Like me, I think a lot of people reduce the spark advance values in the underspeed/overspeed tables to help steady the idle by reducing corrections.
When changing things around that affect idle you may want to unhook the battery each time to erase whatever idle-learn saved during unsuccessful attempts to get the idle right.
I'm not 100% positive but I don't think the learned idle values are erased during a re-flash. From what I've observed it looks like you have to unhook the battery to clear those.
Like me, I think a lot of people reduce the spark advance values in the underspeed/overspeed tables to help steady the idle by reducing corrections.
