Fuel trims

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Sep 5, 2012 | 02:29 PM

tomj77

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From: canada

Fuel trims

So what should I want my lfts to be. Think I got that right. I was at 7.8 with k&n then I retuned to the new trifecta tune that take maf out of the equation , now I'm at -6.4

Sep 5, 2012 | 02:31 PM

Frogstofall

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That's still off. I think most tuners like them to be +/- 1 or as close to 0 as possible.

Sep 5, 2012 | 02:39 PM

TommyP

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after tuning my LTFTs were right around +/- .7 at all times. You want it as close to zero as possible.

Sep 5, 2012 | 03:15 PM

slapbetcommissioner

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Just GMS1 with a K&N SRI im usually about +/-3 usually and at worst 5-8 and thats only for a couple seconds

Sep 5, 2012 | 03:40 PM

ItalianJoe1

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A couple percent while driving isn't a big deal. Log it again and send it back to vince so he can adjust it more, but it's not gonna hurt anything.

Sep 5, 2012 | 03:42 PM

tomj77

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Ya with my Hahn cai I was at worst 3, now with k&n it's off it's rocker. Tried changing filter position, don't work. Still the same

Ya will log it then I guess

Last edited by tomj77; Sep 5, 2012 at 03:42 PM. Reason: Automerged Doublepost

Sep 5, 2012 | 03:57 PM

slapbetcommissioner

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Map sensor could be dirty.
Also was your tune done specifically for the HAHN and now you have a k&N? Or did you get re tuned for the K&N?

Sep 5, 2012 | 04:00 PM

tomj77

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I got it retuned for k&n . Or did I forget to tell him that I had one. He did look at it and said it was good. I'll try again and mention the trims

Sep 5, 2012 | 04:02 PM

tomj77

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I also just switched from 91 octane to 94 with 10% E

Sep 5, 2012 | 04:10 PM

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Frogstofall

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^^Way to leave that tidbit of info out of your original post.

That could very easily skew trims a bit.

Sep 5, 2012 | 04:15 PM

#11

09CobaltSS1

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Any unaccounted for ethanol in the system will cause the trims to swing more to the possative to enrichen the mixture, not negative though..

Sep 5, 2012 | 04:57 PM

#12

tomj77

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It was positive, till I did the tune that disables maf sensor . I'll put that tune back and retune

Sep 5, 2012 | 05:12 PM

#13

Dart_SI

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My trims used to be around +7-8 for some reason. Did an oil change, changed plugs, and seafomed the car and now they are consistent around 1.5. I guess basic maintenance helps is what im getting at.

Sep 5, 2012 | 05:24 PM

#14

SSlobalt

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From: Kathmandu

I've had some negative fuel trims every since I blew my hotside tube off my IC I'm around -2.3 STFT and -0.9 LTFT at cruise. I'm convinced I have a small leak. I just need to stop being lazy and fix it.

Sep 5, 2012 | 05:33 PM

#15

tomj77

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Quote:

Originally Posted by Dart_SI

My trims used to be around +7-8 for some reason. Did an oil change, changed plugs, and seafomed the car and now they are consistent around 1.5. I guess basic maintenance helps is what im getting at.

i just did all that.