But I'm a cheap fawk.
Help me understand my engine map (1.9L ALH) (Or I intend to do stupid things)
- Thread starter Sbeghan
- Start date
TDIJetta99
Top Post Dawg
you speak a LOT of theory.... in practice, that little VNT15 can and will make more than 8psi at 1500rpm and live a very long happy life especially on a stock tune.. You can drive a stock ALH foot to the floor from idle to redline and they just take it and take it as long as there's no sticky vanes or actuator..
That chart you posted looks a lot like a VNT17 compressor map..
robnitro
Veteran Member
The compressor map could be wrong, it came from some thread here, I questioned it on another thread way back because the VB map is almost the same max flow (but higher midrange PR allowable) despite the bigger wheel.
robnitro
Veteran Member
The stock 2003 GN tune doesn't seem to use the boost limit map like many other stock files (and some tuned ones). It's really stupid that they aren't correcting for altitude. That is where I think the TDICLUB faq came up with that lower safe number. Just going up to denver, from sea level makes 8 psig go from 1.5 PR up to 1.76 PR.
Stock ECU boost target map, shows:
11 psi at 1500 rpm
12.5 psi at 1743
14 psi at 1911 rpm, maxed out till 4200 rpm... then it goes down a bit.
Enabled
Veteran Member
So should we be modifying that altitude map? I did, based on atmospheric pressure - max boost... but I was also wanting to know if there was another map that compensates for the lack of correction for altitude, that we don't yet know about?
robnitro
Veteran Member
I run a smoke limiter that limits my fuel up to around max boost (max flow I can get)... So I primarily use that with boost correction- less boost- less maf, less fuel.
The other map that lets you limit fuel based on altitude is the torque limiter... see at the axis 1000, 850, 700 etc.. I also used that map but set it a bit higher than max fueling expected. I like smoke limiter as my lowest limit, so I am smoke free.
(example: if at 2500 I push enough air for 78 mg IQ, I have the torque limiter set for that around 80 or so. Just kind of a fail over, like if you lose boost control or want to limit fueling so it doesn't spike as high.- many variables, many maps, tuning you play around with it)
The other map that lets you limit fuel based on altitude is the torque limiter... see at the axis 1000, 850, 700 etc.. I also used that map but set it a bit higher than max fueling expected. I like smoke limiter as my lowest limit, so I am smoke free.
(example: if at 2500 I push enough air for 78 mg IQ, I have the torque limiter set for that around 80 or so. Just kind of a fail over, like if you lose boost control or want to limit fueling so it doesn't spike as high.- many variables, many maps, tuning you play around with it)
robnitro
Veteran Member
MAP correction for IAT
If anyone is running MAP based tune, you can use this map to correct for temperature.
Someone on ecuconnections noticed smokiness when his SMIC heated up, and I extended it up to 3.6 bar for him.
The midpoint I've seen on most MAP/IAT corrections is 50C, which you see is highlighted... After that the ecu fuels less for same MAP, before that, it can fuel more for same MAP.
If anyone is running MAP based tune, you can use this map to correct for temperature.
Someone on ecuconnections noticed smokiness when his SMIC heated up, and I extended it up to 3.6 bar for him.
The midpoint I've seen on most MAP/IAT corrections is 50C, which you see is highlighted... After that the ecu fuels less for same MAP, before that, it can fuel more for same MAP.
So you're reducing the boost limit at higher temperatures so that the boost comes down, and therefore fueling by way of the smoke map, right?
robnitro
Veteran Member
Iirc, it sends Map smoke limiter the value, a correction.
I dont think it lowers actual boost, but I only used map tune for a few days in summer.
Lets say you do full fueling at 2.5 bar. At 50C you would need 2.5bar map to satisfy the Map smokemap.
But if iat was 10C, you would be getting full fuel at 2.2 bar instead (less lag).
Similar thing with maf, but maf is already self corrected for temperature (though there is a table for temp/maf which I don't know how or why to change it).
I dont think it lowers actual boost, but I only used map tune for a few days in summer.
Lets say you do full fueling at 2.5 bar. At 50C you would need 2.5bar map to satisfy the Map smokemap.
But if iat was 10C, you would be getting full fuel at 2.2 bar instead (less lag).
Similar thing with maf, but maf is already self corrected for temperature (though there is a table for temp/maf which I don't know how or why to change it).
Ah, okay, so the "boost limit" values in this map scale the MAP reading to the other maps.
That makes a lot more sense.
Rob, reading up on MAF stuff from your posts on ECUconnections, and wow, thanks for sharing all that info.
http://www.ecuconnections.com/forum/viewtopic.php?f=2&t=17224
http://www.ecuconnections.com/forum/viewtopic.php?f=2&t=17224
Feinstaub_CH
Veteran Member
Help me understand WHAT does regulate the PD-Unit
Hi all
I will ask here to avoid creating a new thread.
My question is, how does the ECU and or PD-unit know how much ms they have to inject...wait wait - i think i just answered my self this question
Is it the Injection Duration map, who decides how much degrees equals to how much quantity in mg?
Regards
Feinstaub
Hi all
I will ask here to avoid creating a new thread.
My question is, how does the ECU and or PD-unit know how much ms they have to inject...wait wait - i think i just answered my self this question
Is it the Injection Duration map, who decides how much degrees equals to how much quantity in mg?
Regards
Feinstaub
robnitro
Veteran Member
486, in this thread I posted about the map limiter and maf limiter maps.
http://www.ecuconnections.com/forum/viewtopic.php?f=2&t=16272&p=143729#p143729
"On my 012 cp ecu edc 15 Its at 5CBCE 10x16 (maf vs temp correction)
The maf smoke map is at 5C9EC
The map correction is at 5CF2C...
So its after the maf smoke map and before the map correction.
Searching for values of 9000, 8000 etc didn't find it on vagedcsuite. But it is a detected unknown map."
http://www.ecuconnections.com/forum/viewtopic.php?f=2&t=16272&p=143729#p143729
"On my 012 cp ecu edc 15 Its at 5CBCE 10x16 (maf vs temp correction)
The maf smoke map is at 5C9EC
The map correction is at 5CF2C...
So its after the maf smoke map and before the map correction.
Searching for values of 9000, 8000 etc didn't find it on vagedcsuite. But it is a detected unknown map."
I found and changed it using this one of yours: http://www.ecuconnections.com/forum/viewtopic.php?f=2&t=17224#p88470
Changed it out to 15000 max, we'll see what it does. Currently unable to datalog as the scam tool (ha) loses connection as soon as the engine's running.
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robnitro
Veteran Member
Now if you set your smoke map to use values above 1000, it will fuel.
At the time, I was using 1250 as max but my iq never would go to that value even though maf was doing 1250+!
So, you will see now you can use a full smoke map range.
At the time, I was using 1250 as max but my iq never would go to that value even though maf was doing 1250+!
So, you will see now you can use a full smoke map range.
Enabled
Veteran Member
I set my smoke limiter map, and smoke limiter 2 map X-axis to be defined up to higher air flow. My maf sees up to 1270mg/str, so defining it up to that X axis value has let me reach my request of 50mg.
I noticed that my ECU (GN) was reading off the "Smoke Limiter 2" map at address 04D61Ch only, as any changes to "Smoke Limiter" map didn't do anything.
robnitro
Veteran Member
If you don't change the map that does "8000", "9000" and so on, which 486 and I are talking about, you won't get IQ values above what 1000 is specified on your smoke maps.
If its set to 1000 max, Example:
you have 900 set to 50, and 1100 set to 70.
Even with maf 1100+ you will end up fueling 60 max, which corresponds to 1000.
That's what got me confused and into finding out WHY it was doing this, and discovering that 10x16 correction for maf and IAT. (pretty stupid imho, as maf is already IAT corrected- mass airflow!)
Now you correct the top line to be 15000 on axis and all across instead of 10000, you will get the 70 or whatever max you set.
A lot of tunes that I have seen don't seem to mess with that and give full fueling at 850 or 950. Causes smoke for that time period boost is rising to max but already satisfying 950 mg/s for example (around 15 psiG). So that small time from 15 psiG to your max boost- smokeee... then max boost, you can be smoke free.
That was why I had to figure this out, I don't like smoke like that, plus it's a tiny bit of lag to make fueling wait for airflow/boost. Some people don't mind though, but to me smoke = wasted fuel and sooted up vanes lol.
If its set to 1000 max, Example:
you have 900 set to 50, and 1100 set to 70.
Even with maf 1100+ you will end up fueling 60 max, which corresponds to 1000.
That's what got me confused and into finding out WHY it was doing this, and discovering that 10x16 correction for maf and IAT. (pretty stupid imho, as maf is already IAT corrected- mass airflow!)
Now you correct the top line to be 15000 on axis and all across instead of 10000, you will get the 70 or whatever max you set.
A lot of tunes that I have seen don't seem to mess with that and give full fueling at 850 or 950. Causes smoke for that time period boost is rising to max but already satisfying 950 mg/s for example (around 15 psiG). So that small time from 15 psiG to your max boost- smokeee... then max boost, you can be smoke free.
That was why I had to figure this out, I don't like smoke like that, plus it's a tiny bit of lag to make fueling wait for airflow/boost. Some people don't mind though, but to me smoke = wasted fuel and sooted up vanes lol.
And advertising for stricter diesel emissions laws...
Doesn't seem to have made much difference in the butt dyno, but I'm still running a completely stock M/T fuel system.
dieseleux
Théoricien -TDIClub Contributor
I use O2 wide band sensor for always check if i overfuel, i one of the best tools to use in tunning.
Dieseleux
Dieseleux
robnitro
Veteran Member
With the O2 sensor, what are you looking for, some minimum of oxygen in exhaust- meaning complete combustion? Do you have a link to a good wideband O2 system that we could use?
dieseleux
Théoricien -TDIClub Contributor
For custom installation and use with ecu or other system
http://www.innovatemotorsports.com/products/lc1.php
Simple Gauge
http://www.innovatemotorsports.com/products/MTXL.php
Innovate is one make good O2 wide band sensor system for diesel because the band are very large, 8:1 to 99:1 for MTX-L and if i remember correctly is 8:1 to 30:1 for LC1.
Most O2 wide band gauge are built for gaz and the dynamic range stop at 18:1 or 20:1, is low to see correctly how chip tune work.
When you have good tune, you do aprox 18:1 to 22:1 for aprox 50 to 80% TPS and never go down Under 14:1 au 100% TPS on all rpm range.
Another think good with O2 sensor is if you make some black smoke and 02 sensor say lean (over 16:1), you have some trouble with combustion or atomisation of fuel.
Dieseleux
http://www.innovatemotorsports.com/products/lc1.php
Simple Gauge
http://www.innovatemotorsports.com/products/MTXL.php
Innovate is one make good O2 wide band sensor system for diesel because the band are very large, 8:1 to 99:1 for MTX-L and if i remember correctly is 8:1 to 30:1 for LC1.
Most O2 wide band gauge are built for gaz and the dynamic range stop at 18:1 or 20:1, is low to see correctly how chip tune work.
When you have good tune, you do aprox 18:1 to 22:1 for aprox 50 to 80% TPS and never go down Under 14:1 au 100% TPS on all rpm range.
Another think good with O2 sensor is if you make some black smoke and 02 sensor say lean (over 16:1), you have some trouble with combustion or atomisation of fuel.
Dieseleux
Enabled
Veteran Member
Ok I found that map on my GN ecu. It is at 4DBD6h Codeblock 2 (manual) and 6DBD6h Codeblock 1 (automatic).
I changed the max Y-axis and values to 15000, but I suppose we can also do just 12500 since the MAF seems to be good to about 1250 mg/str flow anyways?
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Enabled
Veteran Member
Another point.
This ALH (GN ecu) map below LOOKS to be IQ to Airmass map? I have put a comparison map from another ECU to support my belief.
Looks very much like this map that has been identified from AHU ecu
I don't think we'd have to edit too much here, unless someone wanted some fueling to happen sooner, before reaching these airflow limits?
Or for instance, if you want it to be a limit on smoking, raising the values at your higher fueling to all be at an air limit of 17:1, instead of some 14:1 values (ex: 51mg / 728 = 14.2 ). You can change it to 867 (or 8670 without the conversion factor) and have a hard limit to 17:1 air to fuel ratio.
This ALH (GN ecu) map below LOOKS to be IQ to Airmass map? I have put a comparison map from another ECU to support my belief.
Looks very much like this map that has been identified from AHU ecu
I don't think we'd have to edit too much here, unless someone wanted some fueling to happen sooner, before reaching these airflow limits?
Or for instance, if you want it to be a limit on smoking, raising the values at your higher fueling to all be at an air limit of 17:1, instead of some 14:1 values (ex: 51mg / 728 = 14.2 ). You can change it to 867 (or 8670 without the conversion factor) and have a hard limit to 17:1 air to fuel ratio.
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robnitro
Veteran Member
No you can do 1500 mg/s maf on midrange with 3.x bar if your turbo allowed it... it saturates at higher rpm.
I use up to 1300 column on smoke map (485x 2.7 is about 1300 and I do get that midrange). Past 3500 I cant do that boost safely... and you wont get 485mg/s per bar due to less ve and more emp, limiting flow.
The 1250 or 1375 you see max in vagcom is a diagnostic limit that the ecu doesnt care.
A good sign of saturated maf is when you log maf and map (group 10). Do maf/(map/1000). If it drops sharply below 400 thats a limit... which I cant do, but others using more boost have seen at higher rpm.
Maf basically measures flow mass (kg/h) and divides by rpm to get per stroke.
The maps you posted are odd... the smokemap is rpm axis maf axis and inside values of iq.
I use up to 1300 column on smoke map (485x 2.7 is about 1300 and I do get that midrange). Past 3500 I cant do that boost safely... and you wont get 485mg/s per bar due to less ve and more emp, limiting flow.
The 1250 or 1375 you see max in vagcom is a diagnostic limit that the ecu doesnt care.
A good sign of saturated maf is when you log maf and map (group 10). Do maf/(map/1000). If it drops sharply below 400 thats a limit... which I cant do, but others using more boost have seen at higher rpm.
Maf basically measures flow mass (kg/h) and divides by rpm to get per stroke.
The maps you posted are odd... the smokemap is rpm axis maf axis and inside values of iq.
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Enabled
Veteran Member
Yes its one of the unknown maps. Looks like the IQ to Airmass map. The AHU and AHF engine ecu's also have maps like that in addition to smoke limiter maps. Looks like an additional method to control smoke in an inverse way. But I'm not sure of the units of airflow, mg/str or mg/sec, etc.
robnitro
Veteran Member
I don't know, I think I have seen it on my ecu too (CP) but despite it being "stock" it did nothing. Must be a feature not enabled.
If you find out what it does or how to use it, let us know. But it seems like it's just redundant... a lot of that weirdness, like the driver's wish, which is %throttle and rpm translate to IQ... but cruise needs inverse drivers wish which is IQ and rpm which translates to how much %throttle it puts. A guy on ecuconnections explained that some functions of the ecu, it can't do a reverse lookup, it needs a table to make it quick and easy for it... makes sense.
If you find out what it does or how to use it, let us know. But it seems like it's just redundant... a lot of that weirdness, like the driver's wish, which is %throttle and rpm translate to IQ... but cruise needs inverse drivers wish which is IQ and rpm which translates to how much %throttle it puts. A guy on ecuconnections explained that some functions of the ecu, it can't do a reverse lookup, it needs a table to make it quick and easy for it... makes sense.
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Sbeghan
Veteran Member
I know I've kinda abandoned the thread (I walk away from messing with my car for 6-12 months at a time before binging on tuning it). I'm very glad that you're still posting in it robnitro.
I'm going to check the last 26 pages and see if there's any vnt17/gt1749vb compressor maps posted, as well as info on pump voltage maps and different nozzles.
I'm going to check the last 26 pages and see if there's any vnt17/gt1749vb compressor maps posted, as well as info on pump voltage maps and different nozzles.
Enabled
Veteran Member
Wow, OP is finally back. Yes this thread is very very good, and has helped many people, like myself, along the way to tune the ALH to my liking.
A big thank you.
Sbeghan
Veteran Member
I saw that map but wasn't sure about it since it just says GT1749V - I thought that was the VNT15.
I don't think I did much of anything but start the thread. Most of the great info is from other contributors.
Someone bought the VNT17 I was looking at before I did, so now I just need to update my tune with my new nozzles. The talk about the wideband O2 sensors really makes me want one, but they're expensive.
Anyone want to loan me one?
I don't think I did much of anything but start the thread. Most of the great info is from other contributors.
Someone bought the VNT17 I was looking at before I did, so now I just need to update my tune with my new nozzles. The talk about the wideband O2 sensors really makes me want one, but they're expensive.
Anyone want to loan me one?
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