Tuning the IAC Effective Area - MAKE THE SCANNER DO THE WORK!

okay welcome to the guide on IAC tuning or idle air control the whole point of this is to be done after everything is done on your VD table and all your throttle blade adjustments are done and you've got a solid number for your hot numbers go ahead and take a moment to read this if you want to pause it here there's some really good information here and make sure you do all of this before even bothering with this table here's some setups and there's the formula we're gonna plug into the scanner I'll show you how to do that in a second that's the first thing we need to do is have the inputs of dynamic air dynamic air flow we need our idle desired so we see our idle desire to air flow right underneath you you'll see idle air control position we need that to those the three we need add next we're gonna go to maths we need to build a formula for this information to be useful so we're going to go ahead and go to tools math parameters open that we're gonna select a open table let's go to the IEC or what we see I have already have a couple of these in here so um I'm gonna go I just build another one show you how that's done this would be a take two for those out there paying attention so IAC corrected three just call it that make it the abbreviation that and here in the notes I like to go ahead and put what the formula is in English so instead of just numbers so here we go so we know it's gonna be idle desired / so just forward slash and that's gonna be dynamic that's gonna be multiplied by the asterisk by IC position now we actually have to make a formula so we're gonna go to a new variable you come in here I'm gonna go to the first one's gonna be idle desired and that's gonna be airflow so we select that leave it in grams the second spine boom done divide that by dynamic we go dynamic airflow same leave it the same Graham's a second make sure in the same units multiply that by I see so we click new variable again we got idle air we go control position boom and that won't have a drop down don't worry about it let's leave it like that and we're done that's how we build the formula and we're gonna use this and we're gonna plot it on a graph we're going to build shortly build right here in a second alright next we need to add a table to use the swoopy math we just made so we're gonna go ahead and go to grass lamp we'll add a table I'm gonna select our variable which is going or what we're gonna log we're gonna go down to the maths on the very bottom open the user to find it's like the table we just are the formula we just made and it pops right up populates the unit will be nothing decimals are 0 function this is optional um if you guys want to if you really want it find out if you're having issues with this while you're driving you can go ahead and add in a filter here of we're gonna we use throttle position use the throttle position ratio yeah yes sounds good we're gonna set that to percent okay and the reason you do this is because you want to only log the number when the throttle is at zero when the IAC is actually working so we're gonna go ahead and set that to point five it's gonna be less than 0.5 percent now cuz on older cars for some reason especially like mine and many I've seen it's gonna say point oh four point four for the throttle position at zero also dynamic air will be an issue so we're gonna go ahead and only log when dynamic air is under a certain amount so we're gonna go ahead and add that leave it in grams a second um outside the bracket and go less than let's say 30 grams a second that's fine for mine that works for me if it's a asked to be lower for yours select a number that works down on the column axis we're gonna go ahead and log the position of the IC so idle air control position pops up it's like that for the values this is the fun part if we go over to the icy steps for this effective area table we will see we have numbers along the top that goes zero to 120 don't get yourself confused don't even worry about those ignore them on the bottom is what we're looking at so this is actual numbers we want to adjust so we're gonna look at these so we're gonna go zero to the range is 310 so our tables gonna have to reflect that so on the table we're gonna go ahead and just start at say like five and then we go 10 15 20 and here at 20 go ahead and start going 22 24 26 and the more detailed you get the more easier this is going to be but you can always come back later and add more if you need to so this is not something you have to do right off the bat but going like by 1 all the way to 100 but I do recommend going ahead and going by 1 up to about a hundred you'll see why when you go ahead and log this you'll see I i AC control positional go all over the place and you want to get as many as many as you can because if it settles between between say like 34 and if you were home let's say 35 and then we go to 40 and if it settles between 35 and 40 say it's at 37 and just sits at 37 you're going to know what the direction is at that number so that's why you can always come back though let's say it is 37 and you can just put 37 in and then you'll know and it will actually repopulate your table also cell hits we're going to go ahead and select let's say about 20 20 should be a fairly good number to use and that should give us a good average so we'll go through like this and all the way up to 310 and leave it as such and if you look at I've got one already built here so you see it goes by three and then it starts going by one up in the 40 range all the way through 100 and it just keeps on going and from there it starts going by three and well actually in this range it's a 1 still announced going by 3 so this does take you a few minutes to sit down and type through but if this one in particular goes away 3:20 but uh you don't have to go all the way 3:20 but you get the point this is um this is exactly how you build the table just because we're looking for the correction right here and we need to know what's a value 142 is actual so this is what we're gonna do and adjust okay so this is what we're gonna do with the actual numbers we get we're gonna go ahead and this is an old log from an idle tuning session for my IC and as you see here on the numbers jumping around and it's logging along and this is the corrected IC value on the bottom this has been balanced off of your desired versus dynamic so we have our dynamic air flow and then of course we have our idle desired so these two numbers divided times position or getting that correction right along the bottom so we do with these numbers after we're Donald y deposit here do this from a cold start start the car and attempt to not touch the throttle as much as possible what the ISC do the work sometimes you'll have to but remember with the filter in you're not actually going to log anything above 0.5 percent so that is just fine if you have to do that as you see the car starts off cold you know this is actually starting a little bit on I think this was on more of a warm warm start but uh you'll have to do this several times through cold starts to get these numbers justice now once we see these numbers what we're gonna good we're going to do is go to our table we're going to start all the way we're on the left and we're gonna find a value that we have locked so we're gonna look around and see if we got let's see if we have a 45 on the table so we're look at this 45 value right here again ignore the top row we're just looking at this this number here 45 so we'll go I might go ahead and put this in single beep pane so I'm scrolling around on the chart 45 go down under the scanner we're gonna find it and see if we have a 45 or something less so we don't have a 45 but we do have a 47 at 47 the value is fifty five forty eight it's 50 so I can go ahead and guesstimate right around it's gonna be pretty close so I'm actually not gonna adjust this number 45 is fairly solid so but however at 55 let's see if that what that one says we'll go back to the scanner and you just keep going along it's a little click on over to value 55 and that one says it's 52 so we'll go back to those here will change this 55 to a 52 and at this one if you want to bump it up slightly it's fine because this one could be you could probably say that's 47 that's why it's important to get as much data as you can but you did say 47 maybe 48 because it was a little higher at 47 so that's the idea here so um we're trying to get it adjust as closely as possible so let's look at value 61 will go to 61 here this is why it's nice to have the numbers plotted one at a time so as you see what's going on I'm just looking for the correction on one particular block so 61 is gonna be 56 so I go back to the here 61 becomes 5640 so I'm looking at 67 again nor ignoring top so 67 go over to 67 and that's 61 okay too easy and you see the correction it's just gonna start doing this not now if you go back to the this you'll see the nut the slope is still looking pretty good now if you do have some areas where you don't have information you can interpolate this and smooth it out and I get a good guesstimate and it'll get you closer this doesn't have to be precise or exact because it will change day to day with conditions and temperatures as things like that but this is the general method so the next one let's see if we can find an area on here that would be interpolated let's go from let's say 80 you know we'll get see if we count 80 in here seventy-eight or 84 look at those so 78-68 it's full tan off concern that in 68 then from these two you can just do this I'm gonna assume that I don't have the information for this so let's just say that it's real 61 68 we just interpolate now we're go ahead and interpolate the selection and we get a guesstimate and that's kind of how you do it if you have some blank spots so you use a piece of data you got and if you got anything in between you need to fill in or just interpolate it and then he just relog and do it again until you get this pretty fairly on and it'll tell the computer precise adjustment on your I see exactly how much air it's adding versus how much air is taking away this gets to be pretty close and again this is all based on your ve tables so if that's off this isn't gonna work very well this is probably one of the last things you're going to do once you get it down and this is romaine leaf or been able to turn the key and let the car warm itself up it can be real frustrating sometimes but keep at it and keep adjusting your values and again any adjustments to your ve table that's gonna affect this so make sure that you have that dialed in first before you come in here and waste all your time adjusting this and trying to get a accurate air flow estimate for the computer but that's pretty much it that's how you that's pretty much how you do this and again like I said the top row is still a relevant and you just go ahead and change your changing numbers as you got him and that should get you moving in the right direction in the correct way to adjust the IAC [Music] you

Channel: ChopperDoc181

Views: 4,512

Rating: 4.9215684 out of 5

Keywords: Idle, air, control, IAC, GM, HP, Tuners, LS, engine, scanner, formulas, user, math, maths, tuning, cars, chopper, doc

Id: 621bcy3Epzo

Length: 13min 9sec (789 seconds)

Published: Thu Mar 28 2019