^^^ya i thought it was ltft with the maf freq table and stft with the correction table?
^^^ya i thought it was ltft with the maf freq table and stft with the correction table?
Make Corr table all 1's
Log LTFT vs Maf Freq
Log STFT vs Maf Correction
I know this might be noobnees but I'm a bit confused on this LTFT/STFT. These two values are trying to get ACTUAL arf(lambda) to match what is desired(opimal) right? If we lie by changing the amount of fuel it thinks its getting by manipulating the MAF cor and freq tables wont we ultimately starve or over richen the motor? Is there any way to look at what the actual lambda is at a desired load while scanning?
2008 Cobalt SSTC S1
67 RS Camaro 406 ci 12 sec 1/4mi
87 Pachanga22 502ci 500hp
yes, there is a part of this or another thread on how to setup the custom pid to read it. there are also configurations in the sticky config sticky. maybe we can get someone with a good working config to post up their config and the vcm scanner.config file as well. that's the one that holds the custom pids.
We are not trying to lie/fool the ECM, we are actually telling it more of the truth if anything (using those terms). What are are doing is adjusting the MAF freq/cor tables to more accuratly reflect reality and make it so the ECM doesn't need to trim itself to achieve target lambda.
The tables in there were likely developed on some test mule cars or maybe an engine on a stand, who knows... they are good compromise tables for mass amounts of cars. We're just custom tailoring a bit
Originally Posted by quickboat
Re-wrote the entire guide this morning
have you happened to get any of my emails? I know they get forwarded to spam
Thank you very much for your contribution and help on this BYT.Re-wrote the entire guide this morning
nice man, thanks
2008 HHR SS 5-speed
HP-Tuned
Added some good info, check it out!
Added:
After the discussion about unplugging the purge solenoid and how it freezes the LTFT, I decided to try and use that to our advantage. Sure enough, it works like a dream!! When you flash the car the LTFT and STFT sit at 0 until the Cat temp comes over ~500*. So this locks the LTFT at 0 and you just watch what the actual trims are doing. On a 3 hr/way trip over the weekend and logging the whole thing:
*LTFT actually sat at 0 most of the time after plugging the purge solenoid back in!
*STFT didn't go past +/-3%!
*LT+ST vs Maf Freq table was like +/-.5%!!!!
*ST vs Maf Corr table had only a couple +/-1% spots!
Car drove incredibly smooth and I was commanding 20* up top while running a 25psi tune
very nice, i need to try it out
2008 HHR SS 5-speed
HP-Tuned
could you post up the config file?
2008 HHR SS 5-speed
HP-Tuned
Does the car always show 0 for the ltft and stft until 500 degrees in the cat or is that a result from unplugging the ppurge solenoid?
Both. When you unplug the solenoid that makes sure the LT freezes, so if you do it at 0 after a flash... well you get it I hope
Okay that makes sense. I'm going to try this tomorrow night and see if I can get them even better than before.Both. When you unplug the solenoid that makes sure the LT freezes, so if you do it at 0 after a flash... well you get it I hope
Thanks!
Hopefully I don't get laughed at for this...
Are there any ill consequences with regard to making changes to the MAF Freq. table AFTER I've been working on the MAF Correction table?
I'd just zero out the correction table and start over.
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
Gave it a shot (made sure to save my tune) and surprisingly, my STFT's (purge unplugged) after a 180 mile drive went from a previous average of -3 to -5 to -2 to 0.8
Thanks anyway Tom.
Could BYT please update the MAF tuning with the screenshots?
I don't know what PID.6 and PID.7 is...
Only motor
Looks like it's another way of getting STFT's & LTFT's. See attached.
I use sensor 114 & 116.
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
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