FAT idle wont change...can you help?
10-27-2005, 09:00 PM
#6
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Originally Posted by Jimmyz
Connected yes, but turned off.
2 - If you are, are you 100% sure the maf is off and the car is using the secondary table?
3 - Also, are you sure you're changing the right cell?
10-27-2005, 09:10 PM
#7
im doing all the changes for him. we can take 15% out of the ve table, both primary and secondary tables and the damn thing still reads -8.6%. the maf fail frequency is set to zero. should he unplug it and check that out just for the hell of it?
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10-28-2005, 03:28 PM
#13
Originally Posted by Jimmyz
That one is way above my head... 
Oxygen sensors are supposed to read a certain voltage at 14.7 air:fuel. Some say this voltage is 450 mv, others say its 500 mv. For simplicity's sake, lets say 500 mv is normally stoich. Now during normal driving, as the oxygen sensors read greater than 500 mv, the PCM pulls fuel (via STFTs) and the oxygen sensor swings belov 500mv, where the pcm adds fuel again in. This is the normal way of things. The fluctuation keeps your cars fueling very close to 14.7 this way. Now you can change the switchpoints for different airflows. The airflow is translated in a seperate table from g/sec into 16 different airflow modes. Then you can adjust the switchpoints for the different airflows. For instance you can set airflow mode 0 - 4 to something low like 350 mv and this will keep idle leaned up a bit (since the PCM will pull fuel everytime the o2 sensor fluctuates north of 350 mv).
10-28-2005, 06:36 PM
#14
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I am seeing the same thing. In my idle MAP range 50kPa - 55kPa I am always way negative and the longer it idles the worse the realtime data is so it effects the long term data. I can make changes and be in-line with all the data around those MAP points. But once I have to sit in traffic and idle for any length of time it slowly goes further and further negative.
I just took for granted it was because of the 9* of overlap in the cam, bleeding unburnt fuel thru the cylinder. Keep me posted of any luck on this problem. At this point I have a horrible dip in my VE table at those MAP points. Thanks
Dave
I just took for granted it was because of the 9* of overlap in the cam, bleeding unburnt fuel thru the cylinder. Keep me posted of any luck on this problem. At this point I have a horrible dip in my VE table at those MAP points. Thanks
Dave
10-28-2005, 07:00 PM
#15
Originally Posted by DWillTA
I am seeing the same thing. In my idle MAP range 50kPa - 55kPa I am always way negative and the longer it idles the worse the realtime data is so it effects the long term data. I can make changes and be in-line with all the data around those MAP points. But once I have to sit in traffic and idle for any length of time it slowly goes further and further negative.
I just took for granted it was because of the 9* of overlap in the cam, bleeding unburnt fuel thru the cylinder. Keep me posted of any luck on this problem. At this point I have a horrible dip in my VE table at those MAP points. Thanks
Dave
I just took for granted it was because of the 9* of overlap in the cam, bleeding unburnt fuel thru the cylinder. Keep me posted of any luck on this problem. At this point I have a horrible dip in my VE table at those MAP points. Thanks
Dave
Looks like it effected the dynamic air and desired air at idle too but it worked for the FAT idle I believe. I need to give it time to relearn though.
Jim
10-28-2005, 08:07 PM
#17
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What is your idle speed? I am set at 900 rpms. I have just started tuning so I may be able to get this taken care of with some more logging sessions.
With all the possible ways to run (OLSD, CLSD, CL), I have alot of reading ahead to decide which way to go.
With all the possible ways to run (OLSD, CLSD, CL), I have alot of reading ahead to decide which way to go.
10-28-2005, 10:31 PM
#18
I have the f-13 112 +4 and that comes out to 7 degrees overlap. I idle at 850 and really dont have any strange fueling at idle. You guys can take a look at my file if you want, not saying its right or wrong, just that its working for me as far as fueling. Although Im still fightng this damn bucking.
File: http://www.ihearyou.com/~tony/tuning/current
File: http://www.ihearyou.com/~tony/tuning/current
10-29-2005, 11:59 AM
#20
Originally Posted by Jimmyz
Well, I unplugged my MAF and changed that DTC setup back to all unchecked and at 0 w/the MAF still unplugged. Then subtracted 5 from both VE's from 40-60 kPa and 400-1200 rpm. I reset the trims and scanned it, got 1 & 2 @ 50 & 55 kPa at idle!
Looks like it effected the dynamic air and desired air at idle too but it worked for the FAT idle I believe. I need to give it time to relearn though.
Jim
Looks like it effected the dynamic air and desired air at idle too but it worked for the FAT idle I believe. I need to give it time to relearn though.
Jim