Slamrod's RomRaider Adventure
#82
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Im looking through various datalogs of mine and Im seeing the same pattern - a massive increase in MAF voltage fluctuation around 4k RPMs. Im seeing one where the fluctuations there are an entire volt - pretty much inconcievable to me that a healthy MAF would have this behavior, but idk, you guys tell me lol.
#83
I got your message. Hitachi is OEM. This is the one I'm running:
Paid $101 a year ago so it's still pretty close. Great MAF.
I would just call AutoZone and verify the part #, make sure it's MAF0095
But I think you're on to something as the 2014 FSM EC section 191 [MAF] Component Check section under "without Consult" states to watch for linear voltage rise between 2500 and 4k rpm when testing the MAF. Testing the MAF without Consult is pretty limited in the FSM.
Let me know.
Paid $101 a year ago so it's still pretty close. Great MAF.
I would just call AutoZone and verify the part #, make sure it's MAF0095
But I think you're on to something as the 2014 FSM EC section 191 [MAF] Component Check section under "without Consult" states to watch for linear voltage rise between 2500 and 4k rpm when testing the MAF. Testing the MAF without Consult is pretty limited in the FSM.
Let me know.
#84
See here for useful MAF info: https://www.romraider.com/forum/view...14162&p=134955
I'm not surprised to see the noise on the MAF voltage. The ECU obviously filters most of that out as your IPW won't change that drastically. I'll see if I have an old datalog with MAF voltage... Found one
Noisy MAF
I'm not surprised to see the noise on the MAF voltage. The ECU obviously filters most of that out as your IPW won't change that drastically. I'll see if I have an old datalog with MAF voltage... Found one
Noisy MAF
Last edited by freezer; 04-11-2020 at 02:52 PM. Reason: Added MAF log
#85
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See here for useful MAF info: https://www.romraider.com/forum/view...14162&p=134955
I'm not surprised to see the noise on the MAF voltage. The ECU obviously filters most of that out as your IPW won't change that drastically. I'll see if I have an old datalog with MAF voltage...
I'm not surprised to see the noise on the MAF voltage. The ECU obviously filters most of that out as your IPW won't change that drastically. I'll see if I have an old datalog with MAF voltage...
Im honestly just swinging away blindfolded right now, praying to connect with the piñata. All i know for certain is I get dangerously lean at 4k. I just happened to notice that my MAF voltage signal seems to have a lot of fluctuation, and figured maybe that might be the cause of my troubles since I cannot for the love of god figure out another cause. The amount of “noise” drastically increases at the exact point that I am getting the AFR spike around 4k RPM. Its hard to say though, I dont really have a “normal” baseline to compare against. Oscillations in the signal voltage are practically immeasurable at idle, go to between 0.3-0.6v in range during cruise, and at around 4k RPM, the range becomes an entire volt in width. Its also worth noting that if I “skip” the 4k RPM range by shifting down in gears, that this problem doesnt occur. Its only in the 4k range, and it happens in every single one of my logs, including before I started reflashing and was using an Apexi NEO.
In my mind its either this MAF signal noise that is causing the issue, or its another symptom of whats causing my issues.
#86
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Would you happen to have a scale of the noise (y-axis displaying voltage)?I think noise is normal, what Im concerned about is the intensity of the noise. Like whats the voltage at one of those peaks vs one of the neighboring lows?
All i could dig up on google was that noise thats 0.1 or 0.2v in ‘intensity” is normal, but more than that is not. Thats based off some random stranger from some random forum so idk if thats accurate at all.
All i could dig up on google was that noise thats 0.1 or 0.2v in ‘intensity” is normal, but more than that is not. Thats based off some random stranger from some random forum so idk if thats accurate at all.
Last edited by Slamrod; 04-11-2020 at 03:02 PM.
#88
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https://www.filehosting.org/file/det.../Test044-1.log
((Btw, this hosting site is just the first one I saw off google. If you guys know a better way to share .log files Im all ears lol))
Heres a snap of a very brief WOT run, from around 3k RPM to 4k where I let off the throttle because AFRs are going to mars.
Last edited by Slamrod; 04-11-2020 at 03:29 PM.
#90
Would you happen to have a scale of the noise (y-axis displaying voltage)?I think noise is normal, what Im concerned about is the intensity of the noise. Like whats the voltage at one of those peaks vs one of the neighboring lows?
All i could dig up on google was that noise thats 0.1 or 0.2v in ‘intensity” is normal, but more than that is not. Thats based off some random stranger from some random forum so idk if thats accurate at all.
All i could dig up on google was that noise thats 0.1 or 0.2v in ‘intensity” is normal, but more than that is not. Thats based off some random stranger from some random forum so idk if thats accurate at all.
6th gen MAF
5.5 gen MAF
#91
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Heres two quick WOT pulls. Sorry that NDS2 decided to use literally the worst, most painful to look at color possible for representing IPW.
1)
2)
Heres the full .log file of these pulls:
http://s000.tinyupload.com/index.php...93574089861186
I also attached the ROM being used, should be downloadable at the bottom of this post.
Edit: Freezer, my apologies but im still not seeing any Y-axis scale in the two pics you uploaded. I can see what the different colors are, but I dont see any reference to the Y-axis as to what values are being displayed.
Maybe, idk. Its one of Douglas Sands'/CGR's, hes been cranking them out for the better part of this last decade. Plenty of people seem to use it without any such issues so I dont think this is the cause.
1)
2)
Heres the full .log file of these pulls:
http://s000.tinyupload.com/index.php...93574089861186
I also attached the ROM being used, should be downloadable at the bottom of this post.
Edit: Freezer, my apologies but im still not seeing any Y-axis scale in the two pics you uploaded. I can see what the different colors are, but I dont see any reference to the Y-axis as to what values are being displayed.
Maybe, idk. Its one of Douglas Sands'/CGR's, hes been cranking them out for the better part of this last decade. Plenty of people seem to use it without any such issues so I dont think this is the cause.
Last edited by Slamrod; 04-11-2020 at 04:40 PM.
#93
That MAF voltage is messed up. I'd reason it's possibly due to a couple of things:
Megalog viewer shows the "MAX" and "MIN" of each scale on the LHS of the plot, color coded.
Nothing against CGR intakes, but volume of sales doesn't mean much. Most people don't bother to install a wideband, just butt dyno! That and the 2nd gen DE engine performs differently than the old DE, and only in the last 3 years have people been tuning these ECUs properly and not piggyback.
- VIAS interference. The factory puts these things on for a reason, there's additional cost to produce them so you know it's not just for kicks, and in this case it's not emissions! The 2nd gen DE (Maxima intake) has separate settings for each solenoid. Notably, the RPM range for solenoid 'A' is 1400 to 5000 RPM, while the other (smaller) one is 1800 to 3800 RPM. You can't run these independently, but you could try changing the upper limit to 5000 and see if that moves the problem, or potentially eliminates it. Easy thing to check!
- The intake diameter is too large. (you're not using the full range of the MAF, I saw in your other log the max voltage was about 3.6V) This still shouldn't produce the results you're seeing, but in my opinion it's not helping.
Megalog viewer shows the "MAX" and "MIN" of each scale on the LHS of the plot, color coded.
Nothing against CGR intakes, but volume of sales doesn't mean much. Most people don't bother to install a wideband, just butt dyno! That and the 2nd gen DE engine performs differently than the old DE, and only in the last 3 years have people been tuning these ECUs properly and not piggyback.
Last edited by freezer; 04-11-2020 at 06:06 PM.
#95
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Thanks guys. Im thinking its a combination of pretty much all these factors - crappy MAF, VIAS interference, intake resonance issues.. Going to get a new MAF and test the VIAS theory in the meantime.
Im also going to look more into how the 7th gen VIAS operates. I think I have a potential work around for those of us running the swap so that we can make the most of it. Stay tuned!
Im also going to look more into how the 7th gen VIAS operates. I think I have a potential work around for those of us running the swap so that we can make the most of it. Stay tuned!
#96
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Let me know later in the week at some point if you find anything beyond RPM points for the solenoid. For that we can just look in the FSM. Im curious if anyone published any information that goes over ideal RPM points for a car thats tuned - only a dyno day could divulge those figures.
I imagine youre correct to a degree. I cant see it affecting peak HP, but I dont see how tuning would eliminate the low end torque gains. Regardless of tuning, the VIAS is able to change the velocity of air entering the motor. I could just disable it and tune accordingly but having a physical change in intake runner size isnt something tuning can replicate I dont think. In any case, I think I should be able to get the VIAS to operate the same way the 7th gen has it - it should actually be quite easy. The challenging part is going to be figuring out where to set the VIAS points for maximum power, since the stock points are not going to be as effective on a tuned motor. For that I would need to rent a dyno, which as of right now isnt quite on my radar yet. But yeah for now, Im gonna determine if thats whats causing the AFR spike, and probably just disable the solenoid until im able to get 100% VIAS function the way Nissan intended for that manifold rather than the ghetto crap I have going on.
Lol patience my dude, theres nobody on Earth that wants my car tuned more than I do. I have a new Hitachi MAF coming in the mail later this week, so ill pretty much be laying low until Im able to swap that in. But yeah, this isnt a project im going to hang up unfinished, Im grinding this crap out until the very end lol. Its literally the last thing I can do to my car to get more power, I already have every other upgrade or bolt-on. Looking forward to it, because then I can start tidying up all the cosmetic stuff on my car. I feel I should have a car thats actually badass before I make it look badass.
Lol patience my dude, theres nobody on Earth that wants my car tuned more than I do. I have a new Hitachi MAF coming in the mail later this week, so ill pretty much be laying low until Im able to swap that in. But yeah, this isnt a project im going to hang up unfinished, Im grinding this crap out until the very end lol. Its literally the last thing I can do to my car to get more power, I already have every other upgrade or bolt-on. Looking forward to it, because then I can start tidying up all the cosmetic stuff on my car. I feel I should have a car thats actually badass before I make it look badass.
Last edited by Slamrod; 04-13-2020 at 10:06 AM.
#100
I imagine youre correct to a degree. I cant see it affecting peak HP, but I dont see how tuning would eliminate the low end torque gains. Regardless of tuning, the VIAS is able to change the velocity of air entering the motor. I could just disable it and tune accordingly but having a physical change in intake runner size isnt something tuning can replicate I dont think. In any case, I think I should be able to get the VIAS to operate the same way the 7th gen has it - it should actually be quite easy. The challenging part is going to be figuring out where to set the VIAS points for maximum power, since the stock points are not going to be as effective on a tuned motor. For that I would need to rent a dyno, which as of right now isnt quite on my radar yet.
#103
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Youre getting less voltage because everything is exactly the same except for the intake size. The same amount of air gets pulled into the motor, but since the diameter of the tube is wider, the air is less dense, and therefore the sensor has less air passing it then it did previously with the stock MAF tube. Since the sensor sees less air, the ECU determines that less fuel is needed to match that air. This, however, is wrong - you only changed the size of the intake and what the sensor is measuring, NOT the actual amount of air entering the motor.
The result is the same exact amount of air entering your motor now produces a lower voltage on the MAF sensor, tricking the ECU into providing less fuel, and your motor ends up running lean. Lower idle voltage is “normal” if you didnt properly tune your car - its not normal if you did tune properly.
#104
What are you doing for tuning? Did you rescale your MAF table to account for the larger MAF tube?
Youre getting less voltage because everything is exactly the same except for the intake size. The same amount of air gets pulled into the motor, but since the diameter of the tube is wider, the air is less dense, and therefore the sensor has less air passing it then it did previously with the stock MAF tube. Since the sensor sees less air, the ECU determines that less fuel is needed to match that air. This, however, is wrong - you only changed the size of the intake and what the sensor is measuring, NOT the actual amount of air entering the motor.
The result is the same exact amount of air entering your motor now produces a lower voltage on the MAF sensor, tricking the ECU into providing less fuel, and your motor ends up running lean. Lower idle voltage is “normal” if you didnt properly tune your car - its not normal if you did tune properly.
Youre getting less voltage because everything is exactly the same except for the intake size. The same amount of air gets pulled into the motor, but since the diameter of the tube is wider, the air is less dense, and therefore the sensor has less air passing it then it did previously with the stock MAF tube. Since the sensor sees less air, the ECU determines that less fuel is needed to match that air. This, however, is wrong - you only changed the size of the intake and what the sensor is measuring, NOT the actual amount of air entering the motor.
The result is the same exact amount of air entering your motor now produces a lower voltage on the MAF sensor, tricking the ECU into providing less fuel, and your motor ends up running lean. Lower idle voltage is “normal” if you didnt properly tune your car - its not normal if you did tune properly.
#105
1.05 would be +5%, etc. Drive around and try to hit all over the fuel map for a long time.
After you get it really close, then calculate for fuel table. That should be so close that you won't need much manual adjustment.
Last edited by Child_uv_KoRn; 04-14-2020 at 02:25 PM.
#106
Log and run it through this. http://djlab.com/uprev/maf.php
1.05 would be +5%, etc. Drive around and try to hit all over the fuel map for a long time.
After you get it really close, then calculate for fuel table. That should be so close that you won't need much manual adjustment.
1.05 would be +5%, etc. Drive around and try to hit all over the fuel map for a long time.
After you get it really close, then calculate for fuel table. That should be so close that you won't need much manual adjustment.
#107
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Your problem is probably because youre applying the numbers wrong. You have to use the change in area, not the change in diameter - the proportion in change in diameters isnt that much, but the change in area is quite significant. Just look up the formula for finding the area of the circle, do that for both old & new intakes, and use that proportion of change for your MAF scaling.
Last edited by Slamrod; 04-14-2020 at 03:51 PM.
#108
Time - A/F CORR-B1 (%) - A/F CORR-B2 (%) - MAS A/F -B1 (V) - NB-O2 SEN 1-B1 (V) - NB-O2 SEN 1-B1 (V)
Is your idle at 0 correction? Adjust K till it is, then log and calculate maf table. Don't forget to zero out fuel table.
Last edited by Child_uv_KoRn; 04-14-2020 at 07:09 PM.
#109
If you only changed the MAF tube diameter, just rescale the MAF multiplier (aka MAF factor) by the same proportion of change. You could alternatively adjust K (fuel multiplier), it the same math, just moving the numbers around in the equation. You just pick one though, not both.
Your problem is probably because youre applying the numbers wrong. You have to use the change in area, not the change in diameter - the proportion in change in diameters isnt that much, but the change in area is quite significant. Just look up the formula for finding the area of the circle, do that for both old & new intakes, and use that proportion of change for your MAF scaling.
Your problem is probably because youre applying the numbers wrong. You have to use the change in area, not the change in diameter - the proportion in change in diameters isnt that much, but the change in area is quite significant. Just look up the formula for finding the area of the circle, do that for both old & new intakes, and use that proportion of change for your MAF scaling.
Yeah. You only need MAF, corrections and the stock O2s. Forgot that NDS2 doesn't log BFS (so obviously can't calculate fuel table). But it'll work for MAF.
Time - A/F CORR-B1 (%) - A/F CORR-B2 (%) - MAS A/F -B1 (V) - NB-O2 SEN 1-B1 (V) - NB-O2 SEN 1-B1 (V)
Is your idle at 0 correction? Adjust K till it is, then log and calculate maf table. Don't forget to zero out fuel table.
Time - A/F CORR-B1 (%) - A/F CORR-B2 (%) - MAS A/F -B1 (V) - NB-O2 SEN 1-B1 (V) - NB-O2 SEN 1-B1 (V)
Is your idle at 0 correction? Adjust K till it is, then log and calculate maf table. Don't forget to zero out fuel table.
#110
Yeah, that's why it's so lean. It's adding as much fuel as it can. Add 25% to K, see where it's at. Then add/subtract to K again depending on what corrections says. You'll be dead on and can tune maf table (it should be fully driveable but maybe rich).
Last edited by Child_uv_KoRn; 04-15-2020 at 01:16 AM.
#111
I did what you said, MAF g/s not going over 120 and on stock setup on idle 650 rpm gm/s was 2.9 now it's 1.5. I am thinking it's not normal
#112
#114
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So, bad news. Still cannot figure out this AFR spike problem. Replaced the MAF with a brand new Hitachi sensor, which didnt really change anything - either this sensor is bad right out the box, or more likely, its not the real issue. I disconnected the VIAS solenoid to see if that was causing the spike - no change. I even unwired the Apexi NEO unit just in case it was somehow interfering with the signal.
Going to test with the stock intake system and see what happens with that, going to wait til tomorrow since its getting dark and cold and windy now. Idk though guys, Im stumped.
Edit: on a side note, if it does turn out to be an issue with the intake itself (ie; resonance) that isnt exactly the worst thing - as long as it is predictable and repeatable, it can simply be tuned out of the equation. Just would need to 100% confirm that is the cause so I dont get hit with any unhappy surprises.
Going to test with the stock intake system and see what happens with that, going to wait til tomorrow since its getting dark and cold and windy now. Idk though guys, Im stumped.
Edit: on a side note, if it does turn out to be an issue with the intake itself (ie; resonance) that isnt exactly the worst thing - as long as it is predictable and repeatable, it can simply be tuned out of the equation. Just would need to 100% confirm that is the cause so I dont get hit with any unhappy surprises.
Last edited by Slamrod; 04-19-2020 at 03:34 PM.
#116
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As far as headers, you mean like exhaust? Im running cattmans, which have been going faithfully strong since I first got them two maximas ago. Probably the one single part on the entire car that gets me geeked every single time I look at it. One day Ill have to do them justice and get them polished and maybe ceramic coated because right now they are looking their age lol.
#117
We have very similar setups. I've also got Cattmans (only 2 years old!). The main differences are I've got an Injen intake for a 6th gen (slot style) a side branch resonator on my y-pipe (no idea what effect it is having, it's primarily intended to eliminate drone) and am running dual VIAS.
#118
I got your message. Hitachi is OEM. This is the one I'm running:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Paid $101 a year ago so it's still pretty close. Great MAF.
I would just call AutoZone and verify the part #, make sure it's MAF0095
But I think you're on to something as the 2014 FSM EC section 191 [MAF] Component Check section under "without Consult" states to watch for linear voltage rise between 2500 and 4k rpm when testing the MAF. Testing the MAF without Consult is pretty limited in the FSM.
Let me know.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Paid $101 a year ago so it's still pretty close. Great MAF.
I would just call AutoZone and verify the part #, make sure it's MAF0095
But I think you're on to something as the 2014 FSM EC section 191 [MAF] Component Check section under "without Consult" states to watch for linear voltage rise between 2500 and 4k rpm when testing the MAF. Testing the MAF without Consult is pretty limited in the FSM.
Let me know.
"I don’t see a part number on the receipt but it looks like they sold you the incorrect sensor if it is MAF0095. The part number on the sensor should be either a MAF0099 (from 12/2001) or MAF0094 (to 12/2001). The MAF0095 only fits on the Pathfinder which tells me there is a physical and/or tuning difference between the two 3.5L engines for the two different applications. That is most likely why you are having issues with the sensor not reading correctly in the higher RPM range."
Not sure if this is your lean prob but hope this helps you not get the wrong maf.
Thx
Last edited by timbarry; 04-19-2020 at 08:48 PM.
#119
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Hi 0095 is the wrong maf for our car. Its a pathfinder maf. This is why it runs lean at those ranges. I experienced this too as it was labeled as the correct maf on ebay but is incorrect. 0099 Is the correct maf. Here is the quote I got from a Hitachi tech about why fueling was dropping out unexpectedly.
"I don’t see a part number on the receipt but it looks like they sold you the incorrect sensor if it is MAF0095. The part number on the sensor should be either a MAF0099 (from 12/2001) or MAF0094 (to 12/2001). The MAF0095 only fits on the Pathfinder which tells me there is a physical and/or tuning difference between the two 3.5L engines for the two different applications. That is most likely why you are having issues with the sensor not reading correctly in the higher RPM range."
Not sure if this is your lean prob but hope this helps you not get the wrong maf.
Thx
"I don’t see a part number on the receipt but it looks like they sold you the incorrect sensor if it is MAF0095. The part number on the sensor should be either a MAF0099 (from 12/2001) or MAF0094 (to 12/2001). The MAF0095 only fits on the Pathfinder which tells me there is a physical and/or tuning difference between the two 3.5L engines for the two different applications. That is most likely why you are having issues with the sensor not reading correctly in the higher RPM range."
Not sure if this is your lean prob but hope this helps you not get the wrong maf.
Thx
New intake and MAF on the way. Nothing wrong with this intake, it turns out, but new Hitachi MAF0099 is ~250 bucks and new slot style MAFs are under $60 and superior in every regard, so thats the way I am going. I suppose if I found out the voltage table for a pathfinder I could make this sensor work just fine, but at this point, Im over it.
User1, I would strongly recommend you stop using that sensor, or at least stay away from WOT. Pretty sure my “”original”” sensor was replaced with one of these by a previous owner, since both old and new sensors I have right now are doing the same thing. And it probably explains why my original motor ended up blowing, since I never figured out what led to it losing compression... ouch.
I guess I at least have closure now, right? LOL
edit: contacted amazon, they will be pulling that item until the description is accurately updated
Last edited by Slamrod; 04-20-2020 at 10:11 AM.
#120
Hey dude, you have no possible idea how much help you just gave me, thank you. This pretty much explains the root of all my problems with this car...
New intake and MAF on the way. Nothing wrong with this intake, it turns out, but new Hitachi MAF0099 is ~250 bucks and new slot style MAFs are under $60 and superior in every regard, so thats the way I am going. I suppose if I found out the voltage table for a pathfinder I could make this sensor work just fine, but at this point, Im over it.
User1, I would strongly recommend you stop using that sensor, or at least stay away from WOT. Pretty sure my “”original”” sensor was replaced with one of these by a previous owner, since both old and new sensors I have right now are doing the same thing. And it probably explains why my original motor ended up blowing, since I never figured out what led to it losing compression... ouch.
I guess I at least have closure now, right? LOL
edit: contacted amazon, they will be pulling that item until the description is accurately updated
New intake and MAF on the way. Nothing wrong with this intake, it turns out, but new Hitachi MAF0099 is ~250 bucks and new slot style MAFs are under $60 and superior in every regard, so thats the way I am going. I suppose if I found out the voltage table for a pathfinder I could make this sensor work just fine, but at this point, Im over it.
User1, I would strongly recommend you stop using that sensor, or at least stay away from WOT. Pretty sure my “”original”” sensor was replaced with one of these by a previous owner, since both old and new sensors I have right now are doing the same thing. And it probably explains why my original motor ended up blowing, since I never figured out what led to it losing compression... ouch.
I guess I at least have closure now, right? LOL
edit: contacted amazon, they will be pulling that item until the description is accurately updated
Anything else that you think I can help with please lmk.
Last edited by timbarry; 04-20-2020 at 12:47 PM. Reason: add info