Trouble tuning the 0% on the UTEC with 600cc injectors!!!
10-07-2009, 10:25 AM
#21
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What about the fact that I have a rising rate fuel pressure regulator? Essentially I have 50 psi fuel pressure at idle and roughly 60 psi fuel pressure at 0 psi of boost. The stock ecu normally only has to deal with a constant 50 psi in the rail, and fires the injectors accordingly. Now, if you apply a single MAF offset to lets say 3000 rpm then wouldn’t you expect it to be leaner 3000 rpm cruising (high vacuum, maybe 52 psi fuel pressure) and richer at 3000 rpm ~50% throttle (just before boost, 60 psi fuel pressure). Basically I have introduced two variables - bigger injectors and varying fuel pressure, and I don’t think the UTEC is sufficient to trick the stock ecu into behaving nicely with both of these additions with MAF based tuning.
I wish the UTEC would let you use multiple columns for MAF based tuning and also let you run open loop speed density. That way you could have 3 or 4 columns for MAF based tuning in vacuum and then switch to open loop in boost for the remaining 7 or 8 columns.
Has anyone ever tried using the UTEC to control fuel in a standalone fashion 100% of the time with speed density? My Miata only has a MAP sensor (no MAF of AFM) and it runs far better than the G35 (so far). The ecu in the Miata has 3 columns for vacuum and 3 columns for boost - that's it. You could do something similar with the UTEC, and set your mapping values from say -15 to 15 psi so you would have 5 columns of vacuum and 5 columns of boost. Then you could just set your timing to "ECU" for all of the columns in vacuum. The only question I have is what would happen with cold and hot starting, since the UTEC has no provisions for such things...
I wish the UTEC would let you use multiple columns for MAF based tuning and also let you run open loop speed density. That way you could have 3 or 4 columns for MAF based tuning in vacuum and then switch to open loop in boost for the remaining 7 or 8 columns.
Has anyone ever tried using the UTEC to control fuel in a standalone fashion 100% of the time with speed density? My Miata only has a MAP sensor (no MAF of AFM) and it runs far better than the G35 (so far). The ecu in the Miata has 3 columns for vacuum and 3 columns for boost - that's it. You could do something similar with the UTEC, and set your mapping values from say -15 to 15 psi so you would have 5 columns of vacuum and 5 columns of boost. Then you could just set your timing to "ECU" for all of the columns in vacuum. The only question I have is what would happen with cold and hot starting, since the UTEC has no provisions for such things...
10-09-2009, 04:21 AM
#24
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So here is the deal. I had the same problem myself with the APS TT with the 650cc. First things first.
1) Did you update the firmware of UTEC? Which version are you running?
2) Did you update the DBW software?
3) I 've noticed that on ignition you are throwing copy through feature, for 10% column. Try to throw actual degrees there. Did you do than on purpose? I would suggest to start from 30 @2500 to about 24 @max RPM.
4) MAP Minimum Value for Mapping should be about (-3~-4) See also (6)
5) Check your Open loop RPM thresshold. According to your maps should be around 2000?
6) Check/ Adjust OPEN LOOP MAP THRESSHOLD. Go to negative values (-3~4PSI). By doing this you will gain better control to the transition from Vacuum to Pressure. You can have the 10% column adjusted for -3~0 psi and the rest (20~100%) for the boost side.
7) Set Close to Open loop to 2
8) Set Open to Close loop to 1
1) Did you update the firmware of UTEC? Which version are you running?
2) Did you update the DBW software?
3) I 've noticed that on ignition you are throwing copy through feature, for 10% column. Try to throw actual degrees there. Did you do than on purpose? I would suggest to start from 30 @2500 to about 24 @max RPM.
4) MAP Minimum Value for Mapping should be about (-3~-4) See also (6)
5) Check your Open loop RPM thresshold. According to your maps should be around 2000?
6) Check/ Adjust OPEN LOOP MAP THRESSHOLD. Go to negative values (-3~4PSI). By doing this you will gain better control to the transition from Vacuum to Pressure. You can have the 10% column adjusted for -3~0 psi and the rest (20~100%) for the boost side.
7) Set Close to Open loop to 2
8) Set Open to Close loop to 1
Last edited by gecof1; 10-09-2009 at 04:26 AM.
10-09-2009, 06:53 AM
#25
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/\ my only problem with this is that Utec is already low on resolution. If you use some of it when in vacuum then you are hurting your self when you are boosting. The ECU is well capable of handling vacuum so why set the min map value to -3?
I think there is a leak somewhere and that is why he's having problem with idle. I dont think he's having problem with the transition that much nor cruising so setting the min map value that low will not solve the idle problem.
I think there is a leak somewhere and that is why he's having problem with idle. I dont think he's having problem with the transition that much nor cruising so setting the min map value that low will not solve the idle problem.
10-09-2009, 07:11 AM
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/\ my only problem with this is that Utec is already low on resolution. If you use some of it when in vacuum then you are hurting your self when you are boosting. The ECU is well capable of handling vacuum so why set the min map value to -3?
I think there is a leak somewhere and that is why he's having problem with idle. I dont think he's having problem with the transition that much nor cruising so setting the min map value that low will not solve the idle problem.
I think there is a leak somewhere and that is why he's having problem with idle. I dont think he's having problem with the transition that much nor cruising so setting the min map value that low will not solve the idle problem.
In addition the throttle position learning should be made, if not already done. Anyway we can wait and see.
I fully agree you will loose the 10%, but I believe that is enough for treating rest of the boost.
10-09-2009, 09:48 AM
#27
Thanks for the additional ideas. Yes I did update the firmwarea nd DBW software right when I got the UTEC. My open loop rpm threshold is set to 500 rpm. I found that I can make 1 psi of boost as low as 1000 rpm, so I decided I wanted full fuel control when in boost at ANY rpm.
Good news though. Here is an update:
After thinking about it a lot I agree with the fact that my 0% column in not compensating enough for my fuel mods. I believe what is happening is that at light cruise and idle the stock ECU is compensating for the misadjustment of the UTEC, but as soon as I were to give it heavy throttle it would go super rich because the stock ecu just couldn't compensate enough without the help it should be getting from the UTEC. This is why I would go very rich just before boost…then the stock ECU would see that I was going rich and pull even more fuel from that zone, hench why I would go lean during cruise. I'm not sure if the stock ecu goes into it's own open loop settings at a certain TPS but that could also explain why it was compensating at cruise and idle but not under heavy throttle.
So last night I reset the stock ecu with the pedal sequence twice, then disconnected the battery for 15 mintues. After reconnecting the battery, I loaded a new map to the UTEC with -14 in the entire 0% column. I did the ecu reset pedal procedure again, except this time I let off the gas (within 3 seconds) after the CEL went solid and started the car (this then becomes the idle-air relearn procedure). Lo and behold after letting it idle for a while and driving it around the neighborhood, it idles well with A/F in the 15's. The other good news is that my rich stumble under heavy throttle in the transition to boost is almost completely eliminated! I still get a very slight studder sometimes, and I can see the A/F gauge dip into the low 12s briefly, but at least it doesn't peg the gauge at 10 anymore! I might try this procedure again and go to a -16 or -17 to see if I can eliminate the rich spike all together.
I am currently at a -1 for my map threshold and it seems to work pretty well. My minimum and maximum values for mapping are 0 and 10, which actually gives me great resolution (1 psi increments!). Compared to my boosted Miata, which only has 3 map columns for 0-22 psi of boost, the UTEC has 7 times better resolution with my current settings.
One question I have is, what does the UTEC do when your map threshold is lower than you minimum mapping value? I believe it just uses the 10% column for everything in between but I am not positive. So in my case it would use the 10% column for -1 to 1 psi (a range of 2 psi) and then all other columns go in 1 psi increments (1 to 2 psi for 20%, 2 to 3 psi for 30%, etc.). gecof1, I understand what you are saying in comment #6 but technically if I were to set my minimum value for mapping to -3 or -4 like you said in comment #4, then I would actually have the 10%, 20%, AND 30% columns in vaccuum.
I set the 10% to stock ecu timing values on purpose. It's not really necessary to pull any timing at such low boost (0-1 psi) and it also helps me diagnose whether or not transition problems are fuel or timing related since the UTEC takes control of each at different times.
The car does idle a lot better with the A/C on. I would like to bump my idle up to ~800 rpm, but unfortunately I have no way to do so.
I am going to keep fiddling, unfortunately I live in Michigan and it has been raining for the past 4 or 5 days, and its 50 degrees today. I don't really like tuning in such cold temperatures, but at least the UTEC has air temp compensation!
Good news though. Here is an update:
After thinking about it a lot I agree with the fact that my 0% column in not compensating enough for my fuel mods. I believe what is happening is that at light cruise and idle the stock ECU is compensating for the misadjustment of the UTEC, but as soon as I were to give it heavy throttle it would go super rich because the stock ecu just couldn't compensate enough without the help it should be getting from the UTEC. This is why I would go very rich just before boost…then the stock ECU would see that I was going rich and pull even more fuel from that zone, hench why I would go lean during cruise. I'm not sure if the stock ecu goes into it's own open loop settings at a certain TPS but that could also explain why it was compensating at cruise and idle but not under heavy throttle.
So last night I reset the stock ecu with the pedal sequence twice, then disconnected the battery for 15 mintues. After reconnecting the battery, I loaded a new map to the UTEC with -14 in the entire 0% column. I did the ecu reset pedal procedure again, except this time I let off the gas (within 3 seconds) after the CEL went solid and started the car (this then becomes the idle-air relearn procedure). Lo and behold after letting it idle for a while and driving it around the neighborhood, it idles well with A/F in the 15's. The other good news is that my rich stumble under heavy throttle in the transition to boost is almost completely eliminated! I still get a very slight studder sometimes, and I can see the A/F gauge dip into the low 12s briefly, but at least it doesn't peg the gauge at 10 anymore! I might try this procedure again and go to a -16 or -17 to see if I can eliminate the rich spike all together.
I am currently at a -1 for my map threshold and it seems to work pretty well. My minimum and maximum values for mapping are 0 and 10, which actually gives me great resolution (1 psi increments!). Compared to my boosted Miata, which only has 3 map columns for 0-22 psi of boost, the UTEC has 7 times better resolution with my current settings.
One question I have is, what does the UTEC do when your map threshold is lower than you minimum mapping value? I believe it just uses the 10% column for everything in between but I am not positive. So in my case it would use the 10% column for -1 to 1 psi (a range of 2 psi) and then all other columns go in 1 psi increments (1 to 2 psi for 20%, 2 to 3 psi for 30%, etc.). gecof1, I understand what you are saying in comment #6 but technically if I were to set my minimum value for mapping to -3 or -4 like you said in comment #4, then I would actually have the 10%, 20%, AND 30% columns in vaccuum.
I set the 10% to stock ecu timing values on purpose. It's not really necessary to pull any timing at such low boost (0-1 psi) and it also helps me diagnose whether or not transition problems are fuel or timing related since the UTEC takes control of each at different times.
The car does idle a lot better with the A/C on. I would like to bump my idle up to ~800 rpm, but unfortunately I have no way to do so.
I am going to keep fiddling, unfortunately I live in Michigan and it has been raining for the past 4 or 5 days, and its 50 degrees today. I don't really like tuning in such cold temperatures, but at least the UTEC has air temp compensation!
10-09-2009, 10:17 AM
#28
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One question I have is, what does the UTEC do when your map threshold is lower than you minimum mapping value? I believe it just uses the 10% column for everything in between but I am not positive. So in my case it would use the 10% column for -1 to 1 psi (a range of 2 psi) and then all other columns go in 1 psi increments (1 to 2 psi for 20%, 2 to 3 psi for 30%, etc.). gecof1, I understand what you are saying in comment #6 but technically if I were to set my minimum value for mapping to -3 or -4 like you said in comment #4, then I would actually have the 10%, 20%, AND 30% columns in vaccuum.
I am going to keep fiddling, unfortunately I live in Michigan and it has been raining for the past 4 or 5 days, and its 50 degrees today. I don't really like tuning in such cold temperatures, but at least the UTEC has air temp compensation!
You live in Michigan so be ready to tune at colder weather to really get your temp compensation table right. The only way to tune the temp compensation table is to actually tune at that temp.
It is ok to see a little rich condition on transition because you are using the 10% column in vacuum (in your case -1psi). This is why Utec suck on part throttle and around transition area.
10-09-2009, 11:46 PM
#29
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When AC is on the load slightly increase. The RPM also. Thats why you have better iddle. My car used to die at traffic light, witc AC off. I had to increase my iddle.
You should increase RPM iddle 50 to 100RPM.
This is the way to go. The iddle learning will help only for some time.
When engine speed exceeds 3500RPM and injector cycle more than 45% stock ECU goes from closed to open loop
You should increase RPM iddle 50 to 100RPM.
This is the way to go. The iddle learning will help only for some time.
When engine speed exceeds 3500RPM and injector cycle more than 45% stock ECU goes from closed to open loop
10-13-2009, 07:43 PM
#30
OK I have another weird one for you guys. My car runs pretty good now, but I keep having an issue right around 2250 rpm. I hit a lean spot when taking off in first gear, right as the rpm's pass 2250. I reduced the MAF offset at that rpm by 3 points (and 1.5 points in the two adjacent zones) and it helped a lot, but it is still present sometimes. Has anyone had a similar experience? It's strange that my fuel curve likes having such a "hole" in it. It goes like this:
-10
-10
-11
-11
-11
-11
-9.5
-8
-9.5
-11
-11
etc.
Oh and also I put the larger diameter MAF housing back in which is why I had to go down from -14 to -10 to get a good idle. The 3" pipe that my MAF is in now should flow about 9% more air than the stock MAF housing, so that makes sense.
-10
-10
-11
-11
-11
-11
-9.5
-8
-9.5
-11
-11
etc.
Oh and also I put the larger diameter MAF housing back in which is why I had to go down from -14 to -10 to get a good idle. The 3" pipe that my MAF is in now should flow about 9% more air than the stock MAF housing, so that makes sense.
10-14-2009, 08:54 AM
#31
I wonder if this has anything to do with the MAF placement...maybe its getting some turbulent air. Its about 6" past the 2.5 to 3" silicone transition, and about 6" before that transition there is a 90 bend where it goes through the readiator support. I am thinking it might be beneficial to move the transition forward a couple inches, put my BOV further away on the pipe just behind the front grill, and move the MAF a couple inches closer to the TB. that would give me more like 10-12 inches between the MAF and the transition coupler.
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