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LTFTs are pissing me off!

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Old 08-26-2006, 05:58 AM
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Default LTFTs are pissing me off!

I'm sick of LTFT tuning. I can't get the **** between -4 and 0. After five or six scans I still have no luck getting them where they need to be. In some cases, the goddamn numbers get WORSE.

The IAT ranged between 65°F and 75°F, with it mostly being between 70°F and 73°F. ECT was always between 192°F and 196°F. In the two pictures below, you can see what I'm talking about. The boxes highlighted in black are the ones where the LTFT was leaner than before. The purple ones are those that remained the same. I use "Paste Special" -> "Multiply by %" when adjusting the values. Generally I log for 45 miunutes and drive for an hour after each flash. MAF is disabled, PE is disabled, Closed Loop is forced, and LTFTs are reset each time.

Log finished at 4:10am


Log finished at 5:56am


I started at midnight and am too tired to keep playing grab *** with this ****. Why the hell does this **** happen? I'm about to give up.
Old 08-26-2006, 06:24 AM
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Give up and get a Wideband.
Old 08-26-2006, 06:36 AM
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Turn em off. LTFTs suck. I turned mine off and fuel straight from the STFTs. If you get within +/-4 consider it done.
Old 08-26-2006, 08:35 AM
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what year is your car...if its an 98-00 then be sure to copy the primary VE over to the secondary..When the MAF is disabled the computer will use only the secondary table..If its an 01/02 then just use the primary..And keep using the LTFT method,as it is the easiest,but look at your stft values,and keep driving until they are almost all zeroed out,dont reset fuel trims everytime either,just when you start for the day.
Old 08-26-2006, 09:30 AM
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Originally Posted by TAQuickness
Give up and get a Wideband.
Best advice you're gonna hear right there. I tried for months to tune with LTFT's and got fairly close.....or so I thought. Finally bought a wideband and 1 hour later my VE table is 95% dialed in. I was so far off even with my ltft's being between -4 and 0 it's not even funny. They shouldn't even sell tuning software without a wideband in my opinion.
Old 08-26-2006, 11:37 AM
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1. do NOT turn off PE!
2. try using this: http://redhardsupra.blogspot.com/200...dsheet_03.html
3. use filtering, filter out decel, wot-ish moments, low cell count, low/high ect and whatever else you'd consider 'dirty' data.
4. make sure your MAF truly failed over, i've had many people come back and complain that changes dont have the desired effect, and it just turned out that MAF wasn't truly ignored. look for DTC p0103 (IIRC). or to be 100% sure, just pull the plug
5. make sure you get no knock, if you do that's gonna screw with your timing, which is gonna throw off resulting AFR, which is gonnna show in your trims going wacky at random.
Old 08-26-2006, 11:44 AM
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I do have a wideband... from FJO Racing. I actually had it longer than the tuning software and got it for keeping an eye on my A/F while spraying. I just wasn't planning on using it till PE tuning, mainly because I don't understand the write-up for using it during LTFT tuning.

Originally Posted by redtail2426
what year is your car...
2002

I'll look into wideband tuning some more, but thanks for your all's input!




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