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LTERM fuel trims @ idle????

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Old May 6, 2002 | 06:33 PM
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Default LTERM fuel trims @ idle????

shoud they be @ 25.0%???
also, i keep getting lean codes (0175?)
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Old May 6, 2002 | 07:18 PM
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Default Re: LTERM fuel trims @ idle????

I really don't think so and you shouldn't be getting lean codes..what are your mods..do you have maft or ls1edit..better fix that problem fast..that lean isn't good for your engine..how is your knock retard..it should be real high also...
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Old May 6, 2002 | 07:32 PM
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Default Re: LTERM fuel trims @ idle????

No. They should not be that high.
What are your other LTRIMs at? Do you have a cam or other engine mods?
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Old May 6, 2002 | 09:38 PM
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Default Re: LTERM fuel trims @ idle????

T1, LS6 intake, ported T/B & maf, FLP headers, and tipical bolt-ons. w/ stock heads, i still made 380rwhp (and lean codes).
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Old May 6, 2002 | 09:54 PM
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Default Re: LTERM fuel trims @ idle????

Mine are about 5% richer than my cruise ltrims. Hence, -1.6% cruise, -6% idle. You're probably getting the lean codes because you've already got the ltrims maxed out at idle, and then the need to get higher while driving.
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Old May 7, 2002 | 07:45 AM
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Default Re: LTERM fuel trims @ idle????

you are probably lean accross the board and need to adjust all your LTRIMs. Did you wideband when you dynoed?
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Old May 7, 2002 | 10:27 AM
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Default Re: LTERM fuel trims @ idle????

25% at idle and a lean code?

25% is the max that pcm can adjust. You have it pegged.

Perhaps try flipping the MAF.

I don't like the Ltrims to be +/-10 or MORE.
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Old May 7, 2002 | 10:46 AM
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Default Re: LTERM fuel trims @ idle????

Your MAF is ported to much
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Old May 7, 2002 | 11:15 AM
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Default Re: LTERM fuel trims @ idle????

its been ported for 4 years. why all the problems now?
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Old May 7, 2002 | 04:21 PM
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Default Re: LTERM fuel trims @ idle????

Glenn, I am having the same issue you are.

https://ls1tech.com/ubb/cgi-bin/ulti...f=23;t=000918.

I am going to replace my 02 sensors and see if that does it. If you fix it please please let me know.
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Old May 8, 2002 | 12:17 AM
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Default Re: LTERM fuel trims @ idle????

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">T1, LS6 intake, ported T/B & maf, FLP headers</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">You probably didn't have these for the last 4 years. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

Put on a stock MAF, if it dips below 10%, then either LS1Edit for the ported MAF or ditch the ported MAF.

Your MAF is ported, please don't "flip" it as suggested. <img border="0" alt="[guns]" title="" src="graemlins/gr_guns.gif" /> Don't ask why. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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Old May 8, 2002 | 07:14 AM
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Default Re: LTERM fuel trims @ idle????

You've either got a MAF problem or a massive air leak.. are all the clamps tight, etc. on the air coupling between the maf and the tb?

As others have mentioned, +25 is VERY LEAN, and is the max the PCM can do, you could cause some damage if you drive the car like this!
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Old May 8, 2002 | 10:30 AM
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Default Re: LTERM fuel trims @ idle????

Um, + 25% LTRIMS are VERY RICH...is that what you meant?
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Old May 8, 2002 | 11:04 AM
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Default Re: LTERM fuel trims @ idle????

No you are running lean
+ltrims, you are running lean
-ltrims, you are running rich
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Old May 8, 2002 | 11:05 AM
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Default Re: LTERM fuel trims @ idle????

No you are running lean
+ltrims, you are running lean
-ltrims, you are running rich
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Old May 8, 2002 | 03:27 PM
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Default Re: LTERM fuel trims @ idle????

would a larger than required hole in the TB butterfly (AIC count @ 0) be part of the problem? i have the egr removed also (ala GM LS6 intake). i'll swap in another TB plate and see what happens. along w/ checking all the intake connections. thanks guys.
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Old May 9, 2002 | 12:05 AM
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Default Re: LTERM fuel trims @ idle????

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by adam12:
<strong>No you are running lean
+ltrims, you are running lean
-ltrims, you are running rich</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">yup.
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