Running Really Lean at Idle, what to do in Edit to correct?
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From: Des Moines, IA
Running Really Lean at Idle, what to do in Edit to correct? Just installed a TR224/112LSA. I'm still on stock tuning but have Edit on my laptop ready to go. I love the stock idle which seems to idle at around 800(M6), but will probably need to drill the TB to get my IAC counts down. My question is in BLM cell 19, idle AC/off, my LTFT are +4 to +8 in both banks. You can really smell the gas, its almost too nasty.
Which table do I need to scale in Edit to correct this condition at idle. VE, IFR???
Thanks so much.
Which table do I need to scale in Edit to correct this condition at idle. VE, IFR???
Thanks so much.
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From: Houston, TX USA
Re: Running Really Lean at Idle, what to do in Edit to correct? There are a couple ways to do this. First way would be to scale the MAF by around 105%. The second way would be to adjust the injector table by around 104%. Either one of them would bring you in the negative LTFT's.
Good Luck,
Good Luck,
On The Tree
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From: Wichita,Ks
Re: Running Really Lean at Idle, what to do in Edit to correct?
There are a couple ways to do this. First way would be to scale the MAF by around 105%. The second way would be to adjust the injector table by around 104%. Either one of them would bring you in the negative LTFT's.
Second. You need to scale the IFR Table down to get your LTFTs negative. so you would multiply by 95% or 90% etc...
to make the PCM think you have smaller injectors so the pulse width will be longer, i.e. more fuel.
Re: Running Really Lean at Idle, what to do in Edit to correct?
There are a couple ways to do this. First way would be to scale the MAF by around 105%. The second way would be to adjust the injector table by around 104%. Either one of them would bring you in the negative LTFT's.
Good Luck,
Good Luck,
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From: Des Moines, IA
Re: Running Really Lean at Idle, what to do in Edit to correct? OK I haven't done anything yet. But I do have a lot saved emails from the Edit email list and I see 50/50 opinions on whether to raise or lower the IFR to lower LTFT's. I just posted this question on here to see what everyone is still saying about this scenario.
I've also read that since I still have the stock MAF do not touch it, which is what I am planning on doing.
Anyone else want to put their input in on this.
Thanks for the responses so far and hopefully the clarifications.
I've also read that since I still have the stock MAF do not touch it, which is what I am planning on doing.
Anyone else want to put their input in on this.
Thanks for the responses so far and hopefully the clarifications.
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From: Des Moines, IA
Re: Running Really Lean at Idle, what to do in Edit to correct? Follow up on this:
First of all I scaled my IFR by 105%, just to see what happens, I went way lean! I was getting +11 to +12.5.
I then changed them back to stock and then I multiplied by 95% much better this time. I think I might scale it a tad more maybe 93% to see what happens. As I was still in the postitive LTFT's.
First of all I scaled my IFR by 105%, just to see what happens, I went way lean! I was getting +11 to +12.5.
I then changed them back to stock and then I multiplied by 95% much better this time. I think I might scale it a tad more maybe 93% to see what happens. As I was still in the postitive LTFT's.
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From: USA
Re: Running Really Lean at Idle, what to do in Edit to correct? Your were lean (positve values) so if your +5 lean your wanting to go -5 richer which is 95 not 105.
Also you should not touch MAF table, use IFR and frankly I would only tune the IFR for idle (cell 19) if that is only where you are off.
I would NOT drill any holes, you have LS1edit to tune and thus can tune the idle and not band aid fix with drilling.
If you are not getting knock, there is no problem being a bit lean exp if that was with engine hot for it maybe richer from a cold start.
The confusion is you say trims are too lean but your smelling rich gas exhaust, conflicts thus I suspect the methods or scanner to knowing what the fuel trims really are.
Also you should not touch MAF table, use IFR and frankly I would only tune the IFR for idle (cell 19) if that is only where you are off.
I would NOT drill any holes, you have LS1edit to tune and thus can tune the idle and not band aid fix with drilling.
If you are not getting knock, there is no problem being a bit lean exp if that was with engine hot for it maybe richer from a cold start.
The confusion is you say trims are too lean but your smelling rich gas exhaust, conflicts thus I suspect the methods or scanner to knowing what the fuel trims really are.
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From: Des Moines, IA
Re: Running Really Lean at Idle, what to do in Edit to correct? Thanks John.
I was pretty much having +LTFT's across the board in all cells. I have had LT Headers for a year with no tuning at all. I figured I'd get Edit once I installed the cam, well here I am
I just scaled the IFR by 93% and all seems to look really good. Now at WOT they lock into "0" now, and at idle the LTFTs are zero to a tick positive and yes its really hot out. 92 degrees and 100% humidity, got to love IA Summer's.
Now I've got to focus on my WOT now since I have adjusted the IFR table and has messed up my 02 readings. They are now in the 930-965mV at WOT.
I just got to figure out how to adjust this scenario in PEvRPM table and where I adjust?
Any input on this.
Thanks again.
I was pretty much having +LTFT's across the board in all cells. I have had LT Headers for a year with no tuning at all. I figured I'd get Edit once I installed the cam, well here I am
I just scaled the IFR by 93% and all seems to look really good. Now at WOT they lock into "0" now, and at idle the LTFTs are zero to a tick positive and yes its really hot out. 92 degrees and 100% humidity, got to love IA Summer's.
Now I've got to focus on my WOT now since I have adjusted the IFR table and has messed up my 02 readings. They are now in the 930-965mV at WOT.
I just got to figure out how to adjust this scenario in PEvRPM table and where I adjust?
Any input on this.
Thanks again.
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From: Raleigh, NC
Re: Running Really Lean at Idle, what to do in Edit to correct? Don't scale the MAF table on a stock MAF.
Normally, use your Injector Flow Rate (IFR) Table to adjust Long Term Fuel Trims (LTFT's.) Adjust IFR values downward to decrease LTFT; this tells the computer the injector is smaller than what it now believes.
More fuel will be added.
LTFT's will become more negative / less positive.
Normally, use your Injector Flow Rate (IFR) Table to adjust Long Term Fuel Trims (LTFT's.) Adjust IFR values downward to decrease LTFT; this tells the computer the injector is smaller than what it now believes.
More fuel will be added.
LTFT's will become more negative / less positive.
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From: USA
Re: Running Really Lean at Idle, what to do in Edit to correct? stock PE/RPM table uses about a 1.23 value which a commanded AFR around 11.8:1
A value of 1.16 would then command PE AFR at close to 12.6:1 AFR and bring the O2s values down.
A value of 1.16 would then command PE AFR at close to 12.6:1 AFR and bring the O2s values down.
