bmx045 Posted September 6, 2011 Share Posted September 6, 2011 So I'm currently stage 2 with stock intake, I removed the silencer placenta and intake duct over the weekend, made sure everything sealed up proper on the inlet side and charge sides of the system, confident in no boost/vac leaks, logging -20inHg and -21inHg on the prosport elec boost/vac gauge. at idle in neutral no a/c. It was pretty damn hot out over the weekend and did some investigating. Without the duct I noticed my IAT's would not get below 111* while driving, 90* outside temp, and at idle got up to 124*. Needless to say I noticed a count of knock (-1.40) here and there. I put the duct back on and while cruising IAT's got down to 93 and stayed there. So obv it makes a big difference. With the duct on is how I have it now, still no placenta. Here is the LV after a run. Interesting on the fuel trims. Perhaps should I rescale the maf? Either that or I have a pre-turbo leak somewhere, however I checked all the lines high and low and can't find a thing, I'm hitting target boost, and vac is fine, idle is fine. Can a real tiny leak cause this type of a/f variations? For a while after the tune all my a/f learned was within +/-5%.... and recently it started this....adding fuel at the low range. Since resetting the ECU, it's been a bit better but beforehand the variations were -13 and bullshit like that. I know this sounds stupid but at wot the stock wideband was below 11.02...that's all i can say since i dont have a wb02. sorry for the retarded pic, no wifi in the area I was in, I would've just created a SS So I thought of maybe using the RR maf tool, though can't find any instructions on how to, I do not have a wb02. I have a feeling that the airbox was kinked and not flush with the filter when it was tuned, so essentially, this is the stock maf scaling since stock intake during stage 2 tune, and I do not believe maf scaling was adjusted since i had the stock intake when I was tuned.....however if it was kinked, potentially the trims were a bit off. Link to comment Share on other sites More sharing options...
rao Posted September 6, 2011 Share Posted September 6, 2011 5% error is not a big deal. If it bothers you remove half of that percentage from that range of the MAF. Rob IF YOU CARE ABOUT YOUR CAR YOU SHOULD NEVER DRIVE IT Link to comment Share on other sites More sharing options...
bmx045 Posted September 6, 2011 Author Share Posted September 6, 2011 alrighty, that LV is after an ecu reset and a quick wot run, since then I have driven about 100 miles so I will check it later today to see if any was resolved. When I was stg 2 tuned I'm nearly certain my airbox was kinked and not flush sealing with my airfilter, I fixed that over the weekend. So possibly this is the reason for adding fuel? Who knows, I'll see if it's back to the -12 -13 like it was before the reset, if it is then I'll cut it out. I'm just not sure how to use the items on the left column in the RR maf tool. - or are you talking about the values in ecu editor? (volts to g/sec) Link to comment Share on other sites More sharing options...
rao Posted September 6, 2011 Share Posted September 6, 2011 If it is off by 13% then it is an issue. The ECU is expecting 13% MORE air than it is receiving, so check mechanical stuff first, make sure the filter isn't plugged up, etc. and then change the MAF curve in the actual file in that area, check the results. Then rinse and repeat. Rob IF YOU CARE ABOUT YOUR CAR YOU SHOULD NEVER DRIVE IT Link to comment Share on other sites More sharing options...
bmx045 Posted September 6, 2011 Author Share Posted September 6, 2011 perhaps the filter is just dirty. Meh. Theoretically, I shouldn't have to change the maf scaling at all if I only removed the placenta. So what you're saying is, it's expecting 13% more air than it is receiving so that would mean that it's running rich? no? I'm confusing myself now. Link to comment Share on other sites More sharing options...
bmx045 Posted September 6, 2011 Author Share Posted September 6, 2011 "Reads the four A/F Learning #1 stored corrections (A-D) from RAM (and A/F learning #2 for H6 models) and displays them as a 2D table. These are the long-term fuel trims based on feedback from the front O2 sensor in closed loop and are applied in both closed loop and open loop. Positive values indicate the percentage of fuel added, while negative values indicate the percentage of fuel removed." roger that. so essentially it's pulling fuel because it senses an afr richer than it expects. atleast it's not lean, that's all i care about. NSFW, chime in any time here Link to comment Share on other sites More sharing options...
GTTuner Posted September 6, 2011 Share Posted September 6, 2011 Are you running stock injectors and a stock intake? Link to comment Share on other sites More sharing options...
bmx045 Posted September 6, 2011 Author Share Posted September 6, 2011 yes Link to comment Share on other sites More sharing options...
bmx045 Posted September 6, 2011 Author Share Posted September 6, 2011 that learning view was after about 20min of driving after reset after ic pipes tightened up, airbox fixing. I for some reason attributed the wacky trims from an IC pipe leak somewhere. I've yet to see the -12/-13 again, but throughout this whole time I never saw vac issues. Link to comment Share on other sites More sharing options...
rtbrjason Posted September 6, 2011 Share Posted September 6, 2011 I saw enough difference in maf error after removing the resonator to warrant optional rescaling. Based on your D range, you're not going to end up effecting OL fueling regardless of how far off your lower ranges are though, which is mostly what people worry about. In 08 MYs, the ecu will compensate 25% in either direction. Assuming it's not doing that due to a hardware issue you can let it compensate or compensate it yourself by tweaking the scaling. If it was near 25 or even 15 though I would suspect a hardware issue. Link to comment Share on other sites More sharing options...
GTTuner Posted September 6, 2011 Share Posted September 6, 2011 To get a good picture of your MAF scaling (which would be only in open loop, as you probably know) you need to drive about 45 minutes in closed loop to get an accurate reading. Stay out of open loop! Link to comment Share on other sites More sharing options...
bmx045 Posted September 6, 2011 Author Share Posted September 6, 2011 well I did a lot of highway driving yesterday, about 2hrs worth, so i'll check a lv when i get home from work to see where it stands at this moment... Link to comment Share on other sites More sharing options...
bmx045 Posted September 6, 2011 Author Share Posted September 6, 2011 update: lv after 100miles of driving, seems good! Link to comment Share on other sites More sharing options...
bmx045 Posted September 7, 2011 Author Share Posted September 7, 2011 I do vaguely recall my tuner mentioning about my idle AFR's being odd while tuning stg 2, perhaps the airbox was leaking then and he made a change, now that i have fixed that it would show a + adjustment in the first range? Link to comment Share on other sites More sharing options...
B-BGTLimited Posted September 7, 2011 Share Posted September 7, 2011 A few things you may want to change to allow you to see some items better would be to tighten up the load range on your FLKC table so you'll get more resolution. I'm currently set for 0-2.75 as my max load since I doubt I would ever hit over that, also my maf learning table peaks out at 50 instead of 75. I've seen a few recommend doing this, especially on the FLKC table so that you will have a tighter idea of where stuff is happening. If you log the engine load perameter you will see what your peak is and then you can adjust for slightly over that. Link to comment Share on other sites More sharing options...
bmx045 Posted September 7, 2011 Author Share Posted September 7, 2011 how do you do that with LV? or is it map based? I thought LV only shows what ranges have been driven in.... Link to comment Share on other sites More sharing options...
rtbrjason Posted September 7, 2011 Share Posted September 7, 2011 A few things you may want to change to allow you to see some items better would be to tighten up the load range on your FLKC table so you'll get more resolution. I'm currently set for 0-2.75 as my max load since I doubt I would ever hit over that, also my maf learning table peaks out at 50 instead of 75. I've seen a few recommend doing this, especially on the FLKC table so that you will have a tighter idea of where stuff is happening. If you log the engine load perameter you will see what your peak is and then you can adjust for slightly over that. I doubt it's necessary for the FLKC ranges to be changed unless he starts seeing a lot of knock in higher load ranges and is using LV to fix them. The Maf D range being 75 is just the way that tuner tunes. The idea is that you will never hit 75g/s in steady closed loop cruise, so that range will never set or be anything other than 0 and won't effect his closed loop fueling. Link to comment Share on other sites More sharing options...
bmx045 Posted September 7, 2011 Author Share Posted September 7, 2011 thx jay, so, I know you want open loop to remain 0 for trims, but do I even hit 75g/s? How do I know if it's hitting target afr in open loop? C range? Link to comment Share on other sites More sharing options...
B-BGTLimited Posted September 7, 2011 Share Posted September 7, 2011 Its map based, Under Fueling - AF Correction/Learning you'll find A/F Learning #1 Airflow Ranges Mine are 5.6, 10.0, 50 so my ranges are 0-5.6, 5.6-10.0, 10.0-50 and 50+ And under Ignition Timing - Knock Control you'll find, Fine Correction Rows (RPM) you can leave this alone unless your over 5400 quite often... and then there is Fine Correction Columns (Load) Mine is set for 1.0, 1.5, 2.0, 2.5 currently, I may bump that to a peak of 2.75 and average the two middle ones to scale correctly, but I'm not sure if I'm even hitting over 2.5 load yet. I'm currently Stage 2 at 17 PSI. Its confusing but the values in there start as the Max for the Range #1 and the Min for Range #2, so thats why the first number being 1.0 means the first range is 0-1 and the next one will be 1-x depending on the next number you have in line. Took me a second to figure out how it was setup. Link to comment Share on other sites More sharing options...
B-BGTLimited Posted September 7, 2011 Share Posted September 7, 2011 I'm only passing on info I got from the romraider forum, you don't have to do it. Some expanded info on the topic. http://www.romraider.com/forum/viewtopic.php?f=33&t=4899 Link to comment Share on other sites More sharing options...
B-BGTLimited Posted September 7, 2011 Share Posted September 7, 2011 thx jay, so, I know you want open loop to remain 0 for trims, but do I even hit 75g/s? How do I know if it's hitting target afr in open loop? C range? Open loop there should be no adjustments being made since those are closed loop adjustments your looking at. For open loop you really need to have a wideband there so you can see the actual A/F ratio and ensure that the MAF tables are providing the proper scaling to give enough fuel. At least thats how I do it on my beretta, I have yet to change the open loop fueling on my Legacy so I'm not positive on if you do the same and scale the top half of the maf sensor to give it more fuel. Someone please correct me on that one if I am wrong. Link to comment Share on other sites More sharing options...
rtbrjason Posted September 7, 2011 Share Posted September 7, 2011 thx jay, so, I know you want open loop to remain 0 for trims, but do I even hit 75g/s? How do I know if it's hitting target afr in open loop? C range? You want them to be as close to 0 as possible, but they will fluctuate with weather changes to some degree and you shouldn't really worry too much about A, B or C ranges unless they get really high and stay there. The D range in the one everyone is usually worried about, as whatever number is in this range gets applied to the rest of the MAF in open loop. That means that if you're running 11:1 a/f at wot and you have -10% in the D range, your 11:1 could be more like 12:1 which is too lean and can cause knock and engine damage. In the case of your tune, the tuner has set the D range so high, that it will never set and should never be anything but 0. You most likely will not hit 75g/s in open loop. I hit 60 or 70g/s while driving steady at 75mph going up hill. Anything more goes into open loop. Without steady drive time at a given g/s, the range won't move from 0. Since you won't be hold 75g/s it should always be 0. Link to comment Share on other sites More sharing options...
bmx045 Posted September 7, 2011 Author Share Posted September 7, 2011 well i ended up putting the silencer back in per recommendation by my tuner, apparently there is hard evidence that the silencer changes maf readings and yeilded changes in afr plus a 10-15whp/tq decrease pre/post silencer dyno runs. i believe previous year lgt airbox's responded differently Link to comment Share on other sites More sharing options...
rtbrjason Posted September 7, 2011 Share Posted September 7, 2011 well i ended up putting the silencer back in per recommendation by my tuner, apparently there is hard evidence that the silencer changes maf readings and yeilded changes in afr plus a 10-15whp/tq decrease pre/post silencer dyno runs. i believe previous year lgt airbox's responded differently I don't disagree and have seen the evidence myself. Not sure about the 10-15 whp loss, but can't dispute it either. Is your maf scaling table on your current rom 100% stock and were you running an oem paper filter at time of tune? Link to comment Share on other sites More sharing options...
bmx045 Posted September 7, 2011 Author Share Posted September 7, 2011 Well, during the tune the intake and filter was 100% stock, so I will stick with it. and it seems maf scaling was altered based on comparison of other maps, 0.90v correlates to 1.30 g/s currently Link to comment Share on other sites More sharing options...
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