Dezod APR X1 Inline ECU Tuning Q&A
08-04-2010, 11:38 PM
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Dezod APR X1 Inline ECU Tuning Q&A
Alright now we have somewhere to share tips ask questions and help each other out with tuning on the new hotness.
Somethings ive noticed are the Inj Adj table is very important and very fickle it absolutely has to be tuned in all aspects or you will think you got a crappy ems most stutters misses and surges are caused by the FTs being off and this table is the key to curing it. Ive also noticed when you account the STFTs and LTFTs for any certain point or cell in InjAdj table you are better off to get it close then have multiple reads of the two at the same point and use the average of the multiple STFTs and LTFTs combined for the outcome of that particular cell. Dont just rely on one reading use an average of multiple readings ive found it is alot more accurate. Paul taught me that oscillation of the timing curve at low rpms is normal and that is how our ecu finds the best outcome. He also showed me that the same oscillation or short up and down spikes or jagged areas in higher rpms is for sure knock adjust and datalog and adjust again if need be. Ive also noticed InjPortSize is always goin to be way lower than the actual injector size on larger injectors. Im runnin 850s and im at 602 in that table. Also if in your InjAdj table you notice your takin a huge amount of fuel out at lower RPMS and KPA you can take the InjPortSize to its leanest point 0 to +5 to help with this dont go to much though cause it will throw cels. Now when you start out on the InjAdj table youll be thinkin jeeze why am i takin out .2 of fuel at certain points dont worry about it its normal and if the stock ecu is tellin you to do it than do as it says Its never wrong. Paul also showed me that when getting the APR to smoothly take over for the stock ecu you not only need to use the FuelTimeFBE section but also fueltpsfb section and get them to work together of course when he did it it took like two seconds but you will have to try a few combos to see what works best. In order to see how the apr taking control is going watch your fuel section in your datalogs and you will see what the apr trys to compensate for whether excessive fuel or lack there off when it kicks in.
Some things that im getting ready to try is the restrikes function really we dont need it unless you have some outrageous cam profile our built engine. It works just as the msd 6a does with some slight differences. What im goin to try is base the spark events the same as a 6a. 6As actually use several different IGN Modules that take over for each other at certain RPM points IE 600-1200rpms module sparks 4 times per event 1200-2200rpms module sparks 3 times per event 2200-3400 rpms module sparks 2 times per event and so on and so forth. 6As are really only necessary on those big cammed big blocks that idle horribly they really make a difference in such a setup but i wanna see what this ecu is capable of. So why not try.
Some questions i have would be for afriat and afrect tables if i add one to a cell does that directly drop the afr one point richer or is it a deviation of one point? Like say 1 in a cell makes the afr when it reaches that temp drop by .5 of an afr point off the point your running at the particular time you hit the temp?
OK my hands hurt time to take a rest
Any Inputs Suggestions or Help would really bring this thread alive
Somethings ive noticed are the Inj Adj table is very important and very fickle it absolutely has to be tuned in all aspects or you will think you got a crappy ems most stutters misses and surges are caused by the FTs being off and this table is the key to curing it. Ive also noticed when you account the STFTs and LTFTs for any certain point or cell in InjAdj table you are better off to get it close then have multiple reads of the two at the same point and use the average of the multiple STFTs and LTFTs combined for the outcome of that particular cell. Dont just rely on one reading use an average of multiple readings ive found it is alot more accurate. Paul taught me that oscillation of the timing curve at low rpms is normal and that is how our ecu finds the best outcome. He also showed me that the same oscillation or short up and down spikes or jagged areas in higher rpms is for sure knock adjust and datalog and adjust again if need be. Ive also noticed InjPortSize is always goin to be way lower than the actual injector size on larger injectors. Im runnin 850s and im at 602 in that table. Also if in your InjAdj table you notice your takin a huge amount of fuel out at lower RPMS and KPA you can take the InjPortSize to its leanest point 0 to +5 to help with this dont go to much though cause it will throw cels. Now when you start out on the InjAdj table youll be thinkin jeeze why am i takin out .2 of fuel at certain points dont worry about it its normal and if the stock ecu is tellin you to do it than do as it says Its never wrong. Paul also showed me that when getting the APR to smoothly take over for the stock ecu you not only need to use the FuelTimeFBE section but also fueltpsfb section and get them to work together of course when he did it it took like two seconds but you will have to try a few combos to see what works best. In order to see how the apr taking control is going watch your fuel section in your datalogs and you will see what the apr trys to compensate for whether excessive fuel or lack there off when it kicks in.
Some things that im getting ready to try is the restrikes function really we dont need it unless you have some outrageous cam profile our built engine. It works just as the msd 6a does with some slight differences. What im goin to try is base the spark events the same as a 6a. 6As actually use several different IGN Modules that take over for each other at certain RPM points IE 600-1200rpms module sparks 4 times per event 1200-2200rpms module sparks 3 times per event 2200-3400 rpms module sparks 2 times per event and so on and so forth. 6As are really only necessary on those big cammed big blocks that idle horribly they really make a difference in such a setup but i wanna see what this ecu is capable of. So why not try.
Some questions i have would be for afriat and afrect tables if i add one to a cell does that directly drop the afr one point richer or is it a deviation of one point? Like say 1 in a cell makes the afr when it reaches that temp drop by .5 of an afr point off the point your running at the particular time you hit the temp?
OK my hands hurt time to take a rest
Any Inputs Suggestions or Help would really bring this thread alive
08-05-2010, 03:01 AM
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DTC p0136 and p0137 these DTCs have reared there ugly heads for about a month while tuning the APR. p0136 mostlythan p0137. p0136 defintition is Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 2). This code happens if the INJADJ table is not set to the ecu acceptable 0 to +-5 FTs at any KPA and RPM point while in steady state. Mostly in the points Paul outlined for us in his right up idle 45mph and 65mph steady states. But if you drive a certain KPA and RPM point steady state that isnt 45 or 65 from day to day it will throw these DTCs if you havent set the INJADJ table in that point to meet acceptable FTs for the ecu. My theory on this is as follows the stock ecu is now seeing that the 2nd o2 reads ~14.65:1 A/F at all times no matter what is going on thanks to the APR. If you drive a steady state of say 50mph in fifth everyday and you havent adjusted the FTs in the INJADJ table for that point the stock ecu sees the off A/F whether it be lean or rich from the first o2 and wants to know why the 2nd o2 is not following suit. The 2nd o2 should deviate with the 1st in the direction it moves to a certain point so after 2 consecutive trips of this happening it thinks the 2nd o2 clearly must be malfunctioning. Moral of the story is if you get the INJADJ table set to the ecus acceptable FTs in that KPA and RPM the code will cease to be.
08-05-2010, 01:01 PM
#4
I hate to say it but threads like this really shouldnt be necessary
This unit was represented as VERY self tuning and it seems like quite a few are having trouble with it. It has also surfaced that it was made for the Toyota 4.0L.
I will hold my breath for AEM
This unit was represented as VERY self tuning and it seems like quite a few are having trouble with it. It has also surfaced that it was made for the Toyota 4.0L.
I will hold my breath for AEM
08-05-2010, 11:11 PM
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I always knew the ecu was made for the tacoma before i even purchased it just like the aem was for something and just like the fic is universal. I was never misled by anyone about that. Common sense carries people a long way. As far as self tuning there will never be a ecu you plug in and boom its tuned. The apr does actually self tune and adjust to the afr u put in any cell. i had my injadj tables off by 20% to lean and when i did my first run the apr saw this and added 20% more fuel to bring the afr to the ratio i had in the afr cells. But that doesnt mean leave it like that it means you should tune it better in those spots to make the fueling seemless. Our stock ecu self learns and tunes but would u use it for a forced induced application. Anyways this thread is for helpin eachother out. not for feedback that is for Dons thread. And do you even have an apr if you havent seen what this can do and does do than your opinion does not help us who own one.
08-06-2010, 03:53 AM
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thats what it was made for. but you know paul he can figure out ways to do pretty much anything. i wish i could have got something like this to work with my first car i probably would have never got rid of it
08-06-2010, 03:37 PM
#8
DTC p0136 and p0137 these DTCs have reared there ugly heads for about a month while tuning the APR. p0136 mostlythan p0137. p0136 defintition is Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 2). This code happens if the INJADJ table is not set to the ecu acceptable 0 to +-5 FTs at any KPA and RPM point while in steady state. Mostly in the points Paul outlined for us in his right up idle 45mph and 65mph steady states. But if you drive a certain KPA and RPM point steady state that isnt 45 or 65 from day to day it will throw these DTCs if you havent set the INJADJ table in that point to meet acceptable FTs for the ecu. My theory on this is as follows the stock ecu is now seeing that the 2nd o2 reads ~14.65:1 A/F at all times no matter what is going on thanks to the APR. If you drive a steady state of say 50mph in fifth everyday and you havent adjusted the FTs in the INJADJ table for that point the stock ecu sees the off A/F whether it be lean or rich from the first o2 and wants to know why the 2nd o2 is not following suit. The 2nd o2 should deviate with the 1st in the direction it moves to a certain point so after 2 consecutive trips of this happening it thinks the 2nd o2 clearly must be malfunctioning. Moral of the story is if you get the INJADJ table set to the ecus acceptable FTs in that KPA and RPM the code will cease to be.
08-06-2010, 03:42 PM
#9
Common sense carries people a long way. As far as self tuning there will never be a ecu you plug in and boom its tuned. The apr does actually self tune and adjust to the afr u put in any cell. i had my injadj tables off by 20% to lean and when i did my first run the apr saw this and added 20% more fuel to bring the afr to the ratio i had in the afr cells. But that doesnt mean leave it like that it means you should tune it better in those spots to make the fueling seemless. Our stock ecu self learns and tunes but would u use it for a forced induced application. Anyways this thread is for helpin eachother out.
There is also a pattern that evolves on the injadj table as you progress through it. The faster the pattern rolls into your view, you can make some good guess and just tweak from there. Once you get the injadj table within IMO -5 to 0 overall, the unit is crisp as can be. It's astounding, quite frankly.
08-06-2010, 03:43 PM
#10
08-06-2010, 03:46 PM
#11
Some questions i have would be for afriat and afrect tables if i add one to a cell does that directly drop the afr one point richer or is it a deviation of one point? Like say 1 in a cell makes the afr when it reaches that temp drop by .5 of an afr point off the point your running at the particular time you hit the temp?
08-06-2010, 04:59 PM
#12
i'll read more about it.. after putting huge tires thats almost weighs 100lbs each wheel+tire im kinda wanting my power back that was robbed from me lol.. maybe ill go s/c route this time though
08-06-2010, 05:02 PM
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The AFR feedback for IAT and ECT are close to what you have in the table. A value of 1 for a particular ECT or IAT will provide about a 1 AFR point richer for the said given value and load. It's not exact, but close. Try it out in a known area where you may be running say 11.7:1 at WOT. Throw some 1s in either table and watch the AFR plummet.
08-11-2010, 09:06 AM
#14
I have a few questions about tuning the X1.
1) Should the X1's air load % match the ECU's absolute load %?
2) Should both or either of these load percentages equate to kPA?
3) When determining the optimal MafID setting, should you look at load % or MAF airflow?
4) What would cause my idle AFR to get continually leaner as IAT increases? I can't find an air leak and the problem is especially bad at low (<800rpm) idle speeds with the A/C off. A/C on and it's not really a problem. I can tune my fuel trims to an average of 0% and still have +20% at low idle when hot. Cold engine idle trims are normal.
I have some ideas but I'd like some opinions. If my PCV valve was stuck closed, could the extra unmeasured air cause this? Is it possible that my IAT sensor is getting heat-soaked from high underhood temps but the post-IC air is actually cooler/denser? Could this have something to do with my fuel inijectors? My oem inj's have 12 ohm impedence and my 440cc DWs have 14 ohm. Unfortunately I don't have any data logs with stock inj's but I do have a log taken when my car was stock except for the inj's and it shows that even with the stock airbox, fuel trims were 10% higher than average at idle.
As for answers I can say that the X1's MafID setting is counter-intuitive. It appears that Tacomas and FJs with a 74mm MAF tube run best with the X1 MafID set to 65mm. TCs with 60-64mm tubes work well set to 65mm and the 71mm XB2 runs well set to 73mm. My MAF tube is 66mm but works best with MafID set to 73-76mm (still working on finding the optimal setting). When I set MafID lower than 73mm my ECU sees more airflow than the X1. I expected it to work the opposite way by compensating for an inflated MAF signal by reducing it and certainly not by inflating it even more.
BTW, just for giggles I set my MafID to 70mm and 80mm today and compared airflow readings between the X1 and ECU at idle to 2000rpm. At 70mm the ECU read about 10% higher and at 80mm it read about 10% lower.
1) Should the X1's air load % match the ECU's absolute load %?
2) Should both or either of these load percentages equate to kPA?
3) When determining the optimal MafID setting, should you look at load % or MAF airflow?
4) What would cause my idle AFR to get continually leaner as IAT increases? I can't find an air leak and the problem is especially bad at low (<800rpm) idle speeds with the A/C off. A/C on and it's not really a problem. I can tune my fuel trims to an average of 0% and still have +20% at low idle when hot. Cold engine idle trims are normal.
I have some ideas but I'd like some opinions. If my PCV valve was stuck closed, could the extra unmeasured air cause this? Is it possible that my IAT sensor is getting heat-soaked from high underhood temps but the post-IC air is actually cooler/denser? Could this have something to do with my fuel inijectors? My oem inj's have 12 ohm impedence and my 440cc DWs have 14 ohm. Unfortunately I don't have any data logs with stock inj's but I do have a log taken when my car was stock except for the inj's and it shows that even with the stock airbox, fuel trims were 10% higher than average at idle.
As for answers I can say that the X1's MafID setting is counter-intuitive. It appears that Tacomas and FJs with a 74mm MAF tube run best with the X1 MafID set to 65mm. TCs with 60-64mm tubes work well set to 65mm and the 71mm XB2 runs well set to 73mm. My MAF tube is 66mm but works best with MafID set to 73-76mm (still working on finding the optimal setting). When I set MafID lower than 73mm my ECU sees more airflow than the X1. I expected it to work the opposite way by compensating for an inflated MAF signal by reducing it and certainly not by inflating it even more.
BTW, just for giggles I set my MafID to 70mm and 80mm today and compared airflow readings between the X1 and ECU at idle to 2000rpm. At 70mm the ECU read about 10% higher and at 80mm it read about 10% lower.
08-11-2010, 07:23 PM
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I have a few questions about tuning the X1.
4) What would cause my idle AFR to get continually leaner as IAT increases? I can't find an air leak and the problem is especially bad at low (<800rpm) idle speeds with the A/C off. A/C on and it's not really a problem. I can tune my fuel trims to an average of 0% and still have +20% at low idle when hot. Cold engine idle trims are normal.
Sounds like you are experiencing heat soak as your MAF which contains the IAT sensor is located pre turbo. The IAT is telling the ECU that the incoming air is hot, thus being less dense and requiring less fuel. As an aside it will also retard the timing slightly to prevent the hot thin air from causing detonation. Retarding timing has the effect of leaning a mixture out. Your o2 sensor sees a lean mixture and wants to add fuel. You see this when it's hot because that is when the ECU has entered closed loop fuel control and the o2 sensor is now accurately measuring o2 content of your exhaust. Since at this point the ECU takes the information from the o2 sensor as a direct result of combustion and the IAT as a slight modifier it heavily weights its decision on what fuel to deliver based on o2 content. Timing altered accordingly to things like IAT and ECT.
You can verify this by recording the temperature readings and timing readings when this occurs.
I have some ideas but I'd like some opinions. If my PCV valve was stuck closed, could the extra unmeasured air cause this?
Brett, that's a good question. The PCV is closed under high load. I would like to think that the engineers at Toyota took that into account when programming this car that there would be some blow by. There is probably less fuel accounted for. However when you are under high load or WOT the ECU runs in open loop which relies on pre programmed algorithms and basic information received such as air flow, throttle angle rate of acceleration to calculate the load and thus the fuel and spark timing. To answer your question I would almost assume that a certain percentage of the semi inert combustion blow by was factored into the fuel delivery from the factory. And if not then that's just dumb.
Is it possible that my IAT sensor is getting heat-soaked from high underhood temps but the post-IC air is actually cooler/denser?
Yes, possible. Read above. Ideally IAT should be located in an intake runner as close the the port as possible to pick up all heat from engine bay, pressurizing, squeezing into a small port and heat soak from hot engine parts. However the IAT is not there and the next best location is after the intercooler in a blow through design.
Could this have something to do with my fuel inijectors? My oem inj's have 12 ohm impedence and my 440cc DWs have 14 ohm. Unfortunately I don't have any data logs with stock inj's but I do have a log taken when my car was stock except for the inj's and it shows that even with the stock airbox, fuel trims were 10% higher than average at idle.
As for answers I can say that the X1's MafID setting is counter-intuitive. It appears that Tacomas and FJs with a 74mm MAF tube run best with the X1 MafID set to 65mm. TCs with 60-64mm tubes work well set to 65mm and the 71mm XB2 runs well set to 73mm. My MAF tube is 66mm but works best with MafID set to 73-76mm (still working on finding the optimal setting). When I set MafID lower than 73mm my ECU sees more airflow than the X1. I expected it to work the opposite way by compensating for an inflated MAF signal by reducing it and certainly not by inflating it even more.
Set your MAF iD closest to what makes your setup run best. It thinks it has a 71 mm intake and you have made a 66mm intake, the velocity is going to be higher, however it is a hotwire sensor so it's going to read the amount of voltage it takes to keep that sensor at a steady temp. The most air flow the cooler it gets which translates into more voltage needed to warm it back up..... Same goes for velocity, if you change the ID of the pipe and the velocity goes higher then you are going to read the same change whether or not the airflow actually changed, which over all it wouldn't because the volume is down the velocity is up.
I suggest for your next setup making a blow through maf and the largest intake on front of the turbo you can make. You want as little restriction on the turbo as possible to prevent choking it which will send it into a free spin damaging the bearings. It's like a vacuum cleaner that has a clogged filter. The speed of the motor shoots up but it doesn't suck anything and if done for long enough the air gets hot and the bearings in the motor get wrecked........A turbo is no different. On an intake that small I'd be willing to bet even at 7 psi you are choking the turbo. Not even mentioning the large lip you have in your current intake which can add all kinds of variables to the equation as air passes by it and becomes turbulent or worse supersonic.
BTW, just for giggles I set my MafID to 70mm and 80mm today and compared airflow readings between the X1 and ECU at idle to 2000rpm. At 70mm the ECU read about 10% higher and at 80mm it read about 10% lower.
What does this tell you?
4) What would cause my idle AFR to get continually leaner as IAT increases? I can't find an air leak and the problem is especially bad at low (<800rpm) idle speeds with the A/C off. A/C on and it's not really a problem. I can tune my fuel trims to an average of 0% and still have +20% at low idle when hot. Cold engine idle trims are normal.
Sounds like you are experiencing heat soak as your MAF which contains the IAT sensor is located pre turbo. The IAT is telling the ECU that the incoming air is hot, thus being less dense and requiring less fuel. As an aside it will also retard the timing slightly to prevent the hot thin air from causing detonation. Retarding timing has the effect of leaning a mixture out. Your o2 sensor sees a lean mixture and wants to add fuel. You see this when it's hot because that is when the ECU has entered closed loop fuel control and the o2 sensor is now accurately measuring o2 content of your exhaust. Since at this point the ECU takes the information from the o2 sensor as a direct result of combustion and the IAT as a slight modifier it heavily weights its decision on what fuel to deliver based on o2 content. Timing altered accordingly to things like IAT and ECT.
You can verify this by recording the temperature readings and timing readings when this occurs.
I have some ideas but I'd like some opinions. If my PCV valve was stuck closed, could the extra unmeasured air cause this?
Brett, that's a good question. The PCV is closed under high load. I would like to think that the engineers at Toyota took that into account when programming this car that there would be some blow by. There is probably less fuel accounted for. However when you are under high load or WOT the ECU runs in open loop which relies on pre programmed algorithms and basic information received such as air flow, throttle angle rate of acceleration to calculate the load and thus the fuel and spark timing. To answer your question I would almost assume that a certain percentage of the semi inert combustion blow by was factored into the fuel delivery from the factory. And if not then that's just dumb.
Is it possible that my IAT sensor is getting heat-soaked from high underhood temps but the post-IC air is actually cooler/denser?
Yes, possible. Read above. Ideally IAT should be located in an intake runner as close the the port as possible to pick up all heat from engine bay, pressurizing, squeezing into a small port and heat soak from hot engine parts. However the IAT is not there and the next best location is after the intercooler in a blow through design.
Could this have something to do with my fuel inijectors? My oem inj's have 12 ohm impedence and my 440cc DWs have 14 ohm. Unfortunately I don't have any data logs with stock inj's but I do have a log taken when my car was stock except for the inj's and it shows that even with the stock airbox, fuel trims were 10% higher than average at idle.
As for answers I can say that the X1's MafID setting is counter-intuitive. It appears that Tacomas and FJs with a 74mm MAF tube run best with the X1 MafID set to 65mm. TCs with 60-64mm tubes work well set to 65mm and the 71mm XB2 runs well set to 73mm. My MAF tube is 66mm but works best with MafID set to 73-76mm (still working on finding the optimal setting). When I set MafID lower than 73mm my ECU sees more airflow than the X1. I expected it to work the opposite way by compensating for an inflated MAF signal by reducing it and certainly not by inflating it even more.
Set your MAF iD closest to what makes your setup run best. It thinks it has a 71 mm intake and you have made a 66mm intake, the velocity is going to be higher, however it is a hotwire sensor so it's going to read the amount of voltage it takes to keep that sensor at a steady temp. The most air flow the cooler it gets which translates into more voltage needed to warm it back up..... Same goes for velocity, if you change the ID of the pipe and the velocity goes higher then you are going to read the same change whether or not the airflow actually changed, which over all it wouldn't because the volume is down the velocity is up.
I suggest for your next setup making a blow through maf and the largest intake on front of the turbo you can make. You want as little restriction on the turbo as possible to prevent choking it which will send it into a free spin damaging the bearings. It's like a vacuum cleaner that has a clogged filter. The speed of the motor shoots up but it doesn't suck anything and if done for long enough the air gets hot and the bearings in the motor get wrecked........A turbo is no different. On an intake that small I'd be willing to bet even at 7 psi you are choking the turbo. Not even mentioning the large lip you have in your current intake which can add all kinds of variables to the equation as air passes by it and becomes turbulent or worse supersonic.
BTW, just for giggles I set my MafID to 70mm and 80mm today and compared airflow readings between the X1 and ECU at idle to 2000rpm. At 70mm the ECU read about 10% higher and at 80mm it read about 10% lower.
What does this tell you?
08-11-2010, 07:55 PM
#17
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I do not have this unit but I was just wondering about your pcv question. I am under the impression the air from the pcv/valve cover is mainly exhaust gases and therefore has very little oxygen content to it. I would think you would not have to adjust for it flowing in or not because it will not affect the metered oxygen calculated, just some food for thought.
08-11-2010, 08:05 PM
#19
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1)The APR load % should be ~equal actual load % on the ecm make sure not reading calculated load as thats always wrong.
2)Paul can take that one as he will get all nitty gritty with it
3)Watch the g/s of the maf on the APR and on the ECM at idle 45mph 65mph and WOT and get them to match within 5 g/s and your in
2)Paul can take that one as he will get all nitty gritty with it
3)Watch the g/s of the maf on the APR and on the ECM at idle 45mph 65mph and WOT and get them to match within 5 g/s and your in
08-11-2010, 08:06 PM
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I do not have this unit but I was just wondering about your pcv question. I am under the impression the air from the pcv/valve cover is mainly exhaust gases and therefore has very little oxygen content to it. I would think you would not have to adjust for it flowing in or not because it will not affect the metered oxygen calculated, just some food for thought.
It is not complete exhaust gas which is mostly inert. It contains oil vapor and some combustion by products.
This is the same kind of issue with EGR. When exhaust gas is introduced into the intake tract you need to subtract fuel because that exhaust gas occupies a percentage of space in the cylinder so instead of getting a cylinder of fresh air and fuel you might get a cylinder of 90% fresh fuel/air charge and 10% inert exhaust gas. If you did not subtract an amount of fuel from that you would run extremely rich.