Where to adjust cold idle A/F in LS1Edit??
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On The Tree
Joined: Jan 2002
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From: Suwanee, Georgia
Where to adjust cold idle A/F in LS1Edit?? My C5 runs so rich at cold idle that it burns the eyes.. I can barely let the car warm up in the garage without killing the family pet. This problem disappears completely once the motor warms up.
My MAF calibration is great.. trims are under 2% across the board.
Where is the best table to adjust for this. I am assuming that perhaps the VE might be the best?
I am assuming that the injector table is the wrong table to adjust since my "hot" idle is fine.
Any advice would be appreciated...
[ February 20, 2002: Message edited by: nevrenuf ]</p>
My MAF calibration is great.. trims are under 2% across the board.
Where is the best table to adjust for this. I am assuming that perhaps the VE might be the best?
I am assuming that the injector table is the wrong table to adjust since my "hot" idle is fine.
Any advice would be appreciated...
[ February 20, 2002: Message edited by: nevrenuf ]</p>
12 Second Club
Joined: Dec 2001
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From: Santa Clarita, CA
Re: Where to adjust cold idle A/F in LS1Edit?? I really don't have an answer to your question but it seems like running a bit rich on cold starts is a normal thing, not to be messed with. My cars have always done this as has everyone elses, but to what degreee (even my modified Turbo TA with no cats never watered the eyes on startup! or killed pets for that matter), maybe theoretically sheet is blown out at this stage for a reason, I would go with it just like a human being wants to be at a state of homostatsis so do our cars, anyways I always try to let my cars warm up before I drive them, especially before hammering.
On The Tree
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From: Atlanta
Re: Where to adjust cold idle A/F in LS1Edit?? I haven't played with fuel maps at all, only transmission and ignition maps, so take my advice for what it's worth.
I was just looking in the program. Under the fuel tab, click on Fuel Air Multiplier. It's the open loop fuel tables and has them listed by temperature. You could probably go into the lower temperature cells and at a low load (less than 30, maybe?) and lower the multiplier.
The car is in open loop when it starts up isn't it? Because the O2's haven't warmed up yet. Let us know if this works.
I was just looking in the program. Under the fuel tab, click on Fuel Air Multiplier. It's the open loop fuel tables and has them listed by temperature. You could probably go into the lower temperature cells and at a low load (less than 30, maybe?) and lower the multiplier.
The car is in open loop when it starts up isn't it? Because the O2's haven't warmed up yet. Let us know if this works.
On The Tree
Joined: Jan 2002
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From: Atlanta
Re: Where to adjust cold idle A/F in LS1Edit?? Try lowering the numbers in the power enrichment table, I'll bet that works. You'll notice at 60 degrees it's at 0 and below that is a positive number.
On The Tree
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From: Atlanta
Re: Where to adjust cold idle A/F in LS1Edit?? I'm going to have a conversation with myself if no one minds.
I was just reading the user guide.
This is what it says for Temp/Power Enrichment.
"This table defines the Power Enrichment (additional fuel) that will be added at WOT vs. the coolant temperature when in PE mode"
Doesn't look like that is what we need.
I was just reading the user guide.
This is what it says for Temp/Power Enrichment.
"This table defines the Power Enrichment (additional fuel) that will be added at WOT vs. the coolant temperature when in PE mode"
Doesn't look like that is what we need.
TECH Resident
Joined: Jan 2002
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From: USA
Re: Where to adjust cold idle A/F in LS1Edit?? Once you get your maf calibrated so when it's in closed loop it's not adding or removing fuel, THEN you modify the PE vs rpm to richen or lean out your AFR's.
This is when it ignores the 02 sensor and goes to a richer "Commanded AFR".
Once you get your maf calibrated, if it's too rich at WOT you can pull out some fuel on the PE vs RPM, if it's too lean, add fuel!
I wouldn't mess with the PE vs temp.
[quote]Originally posted by cjones:
<strong>I'm going to have a conversation with myself if no one minds.
I was just reading the user guide.
This is what it says for Temp/Power Enrichment.
"This table defines the Power Enrichment (additional fuel) that will be added at WOT vs. the coolant temperature when in PE mode"
Doesn't look like that is what we need.</strong><hr></blockquote>
This is when it ignores the 02 sensor and goes to a richer "Commanded AFR".
Once you get your maf calibrated, if it's too rich at WOT you can pull out some fuel on the PE vs RPM, if it's too lean, add fuel!
I wouldn't mess with the PE vs temp.
[quote]Originally posted by cjones:
<strong>I'm going to have a conversation with myself if no one minds.
I was just reading the user guide.
This is what it says for Temp/Power Enrichment.
"This table defines the Power Enrichment (additional fuel) that will be added at WOT vs. the coolant temperature when in PE mode"
Doesn't look like that is what we need.</strong><hr></blockquote>
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On The Tree
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From: Atlanta
Re: Where to adjust cold idle A/F in LS1Edit?? I thought you were only suppose to change the MAF table if you changed the MAF to a different one? What if it's still stock, do you still want to calibrate it? If so, how do you do it?
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TECH Resident
Joined: Jan 2002
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From: USA
Re: Where to adjust cold idle A/F in LS1Edit?? The whole function of a MAF Translator is to cause a change to AFR by adjusting the Freq output of MAF.
Maybe MAF is stock but screen is out, or due to airfilter type or using a cold air box, would consider calibrating the MAF table.
I am using a PCM scanner and recording MAF freq, volume in grms/sec, engine load and MAP in Kpa to use as a gulde to the values MAF is outputting, vs what values is in the MAF table.
[quote]Originally posted by cjones:
<strong>I thought you were only suppose to change the MAF table if you changed the MAF to a different one? What if it's still stock, do you still want to calibrate it? If so, how do you do it?</strong><hr></blockquote>
Maybe MAF is stock but screen is out, or due to airfilter type or using a cold air box, would consider calibrating the MAF table.
I am using a PCM scanner and recording MAF freq, volume in grms/sec, engine load and MAP in Kpa to use as a gulde to the values MAF is outputting, vs what values is in the MAF table.
[quote]Originally posted by cjones:
<strong>I thought you were only suppose to change the MAF table if you changed the MAF to a different one? What if it's still stock, do you still want to calibrate it? If so, how do you do it?</strong><hr></blockquote>
TECH Resident
Joined: Jan 2002
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From: USA
Re: Where to adjust cold idle A/F in LS1Edit?? Fuel trim cell 20, but that is not something you can touch and change as what I've seen in LS1-Edit
[quote]Originally posted by sross:
<strong>Isn't there a specific fuel cell for idle?</strong><hr></blockquote>
[quote]Originally posted by sross:
<strong>Isn't there a specific fuel cell for idle?</strong><hr></blockquote>
Teching In
Joined: Jan 2002
Posts: 45
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From: NJ
Re: Where to adjust cold idle A/F in LS1Edit?? Neverenuf,
Well, PE is not the place to work on warmup. The first question, is how long does this last? Do you have a scanner? When you first start the car, it is in open loop until the )2's warm up. That would make me think this is an open loop isue. Can you use a scanner, and see what mode the PCM is in during this rich condition? Also check your Long Term Fuel trims to see if they are near 0.
Ken
Well, PE is not the place to work on warmup. The first question, is how long does this last? Do you have a scanner? When you first start the car, it is in open loop until the )2's warm up. That would make me think this is an open loop isue. Can you use a scanner, and see what mode the PCM is in during this rich condition? Also check your Long Term Fuel trims to see if they are near 0.
Ken
Re: Where to adjust cold idle A/F in LS1Edit?? [quote]Originally posted by cjones:
<strong>I haven't played with fuel maps at all, only transmission and ignition maps, so take my advice for what it's worth.
I was just looking in the program. Under the fuel tab, click on Fuel Air Multiplier. It's the open loop fuel tables and has them listed by temperature. You could probably go into the lower temperature cells and at a low load (less than 30, maybe?) and lower the multiplier.
The car is in open loop when it starts up isn't it? Because the O2's haven't warmed up yet. Let us know if this works.</strong><hr></blockquote>
After re-reading this post, this response makes the most sense to me. I do have a question though... Even though the PCM ignores the O2s at WOT, is it still considered closed loop, or will changes in the Fuel Air Multiplier affect WOT (as well as warm-up)?
<strong>I haven't played with fuel maps at all, only transmission and ignition maps, so take my advice for what it's worth.
I was just looking in the program. Under the fuel tab, click on Fuel Air Multiplier. It's the open loop fuel tables and has them listed by temperature. You could probably go into the lower temperature cells and at a low load (less than 30, maybe?) and lower the multiplier.
The car is in open loop when it starts up isn't it? Because the O2's haven't warmed up yet. Let us know if this works.</strong><hr></blockquote>
After re-reading this post, this response makes the most sense to me. I do have a question though... Even though the PCM ignores the O2s at WOT, is it still considered closed loop, or will changes in the Fuel Air Multiplier affect WOT (as well as warm-up)?
On The Tree
Joined: Jan 2002
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From: Atlanta
Re: Where to adjust cold idle A/F in LS1Edit?? I put an Autotap on a 99 Firebird (M6) with a B1 cam this weekend. It smells rich at idle and at idle it's MAP reading was like 13.9.
To lean it out at idle, shouldn't I go into the V.E. table at MAP 15 and lower the number? The number at MAP 15 @ 800rpm is 1035. If I lower that to 900, does it take 10% fuel out?
I just looked at the V.E. table in my 99 C5 (A4) and at MAP 15 @ 800rpm it has 1120. Why would they be different? Does that mean mine is running richer at idle?
To lean it out at idle, shouldn't I go into the V.E. table at MAP 15 and lower the number? The number at MAP 15 @ 800rpm is 1035. If I lower that to 900, does it take 10% fuel out?
I just looked at the V.E. table in my 99 C5 (A4) and at MAP 15 @ 800rpm it has 1120. Why would they be different? Does that mean mine is running richer at idle?
Staging Lane
Joined: May 2002
Posts: 80
Likes: 6
From: PA
Re: Where to adjust cold idle A/F in LS1Edit?? Wow, sounds like there isn't an answer to start-up enrichment.
I know in aftermarket PCM's that there are enrichment offsets for the following times from startup: 5, 15, 30, 60 seconds.
I have a moded LS1 that goes lean from 30 to 60 seconds after startup.
Very anoying. Needs more "choke."
I know in aftermarket PCM's that there are enrichment offsets for the following times from startup: 5, 15, 30, 60 seconds.
I have a moded LS1 that goes lean from 30 to 60 seconds after startup.
Very anoying. Needs more "choke."
Re: Where to adjust cold idle A/F in LS1Edit?? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by cjones:
<strong>To lean it out at idle, shouldn't I go into the V.E. table at MAP 15 and lower the number? The number at MAP 15 @ 800rpm is 1035. If I lower that to 900, does it take 10% fuel out?
I just looked at the V.E. table in my 99 C5 (A4) and at MAP 15 @ 800rpm it has 1120. Why would they be different? Does that mean mine is running richer at idle?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Anyone else know why the two cars have different values in the tables for the same rpm?
ERic
<strong>To lean it out at idle, shouldn't I go into the V.E. table at MAP 15 and lower the number? The number at MAP 15 @ 800rpm is 1035. If I lower that to 900, does it take 10% fuel out?
I just looked at the V.E. table in my 99 C5 (A4) and at MAP 15 @ 800rpm it has 1120. Why would they be different? Does that mean mine is running richer at idle?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Anyone else know why the two cars have different values in the tables for the same rpm?
ERic
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From: College Station, Tx
Re: Where to adjust cold idle A/F in LS1Edit?? The VE value is different probably because they are different calibrations - changes in the table would reflect either slight changes in the motor, or slight changes in the tune state as desired by GM.
This is/was a source of controversy with LT1's - but on your LS1 I can tell you that the VE table will not effect any change on your tuning unless you are running without a maf at all.
Chris
This is/was a source of controversy with LT1's - but on your LS1 I can tell you that the VE table will not effect any change on your tuning unless you are running without a maf at all.
Chris
