Hugh Posted May 3, 2006 Share Posted May 3, 2006 I am running an SR20DET (2.0 liter) with a huge Infiniti Q45 throttle body. The throttle position sensor from the Q45 doesn't match the SR20DET connector, so for now I am trying to tune out the computer to compensate for it by using MAP sensor rate of change enrichment. Here's a snapshot of my Air/Fuel ratio datalog (sorry its not wired into the Tec3 right now, so you can just see A/F over time) I broke it down in sections to make it obvious whats going on. The Decel area stays at 16:1 or so because the DECEL cut of the injectors is also dependent on the TPS signal being closed. Since there is no TPS, it keeps pumping fuel on decel... resulting in some light popping. (not a problem) The fuel curve in the steady area is fine. I have not taken the time to fine tune it yet, just keeping it in the safe region. I'll get that straight later on. I'm just worried about the point where I punch the throttle, and it spikes to 25:1 for a moment. Here's a snapshot of my MAP enrich settings, its dependent on the highlighted box(ACE 6), as well as the time for variable time Accel enrichments (ACE 4) Any advice on how to set this to make it stop going super lean momentarily? Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 3, 2006 Share Posted May 3, 2006 It would be helpful if you could supply a TEC3 datalog of this same type of situation (doesn't have to be the same run, but it would be nice if it was). I need to see the map signal and the gama (total fpw in TEC3 speak), along with rpm and maybe the coolant temperatures. In general, I'm suspicious of the pressure rate sensitivity - if it's too low, the enrichments won't get triggered. You can try lowering that value, but it would be best to see what is going on and make a more informed decision instead of guessing. Quote Link to comment Share on other sites More sharing options...
Hugh Posted May 3, 2006 Author Share Posted May 3, 2006 Aww, damn. I didn't datalog that on the Tec, just on my Innovate LM1. Let me see what I've got from the Tec. Otherwise I may have to go out for a ride and datalog something new. I will try to post a clean little screen shot like that... but if it don't work out I'll just email you the log session. (assuming you have WinTec3 on your PC) Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 3, 2006 Share Posted May 3, 2006 I will try to post a clean little screen shot like that... but if it don't work out I'll just email you the log session. (assuming you have WinTec3 on your PC) No problem -whatever works for you... Quote Link to comment Share on other sites More sharing options...
Hugh Posted May 3, 2006 Author Share Posted May 3, 2006 Here you go: You can see where the MAP jumps and the RPM takes a moment to rise after that. This is the lag I'm feeling, and the place where the A/F shoots way up. Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 3, 2006 Share Posted May 3, 2006 Here you go: You can see where the MAP jumps and the RPM takes a moment to rise after that. This is the lag I'm feeling' date=' and the place where the A/F shoots way up.[/quote'] Notice that the FPW pretty much didn't do anything when the MAP jumped. This indicates that the sensitivity is too low. Assuming that the timescale is 1 sec per division, it looks like the MAP rate of change is maybe 120 to 150 kPa/sec, or 1.2 to 1.5 kPa/mS. Try setting the MAP sensitivity to around 1.1 and see if you get any better results. Once you see that FPW is responding to the MAP rate of change, then you can start fiddling with the enrichment amounts. Quote Link to comment Share on other sites More sharing options...
Hugh Posted May 3, 2006 Author Share Posted May 3, 2006 Where is the MAP rate of change setting? Are you talking about ACE 4 above? (I have it set at .5 seconds) I've dug around through all the menus and can't find MAP sensitivity. Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 3, 2006 Share Posted May 3, 2006 Where is the MAP rate of change setting? Are you talking about ACE 4 above? (I have it set at .5 seconds) I've dug around through all the menus and can't find MAP sensitivity. ACE1 - Manifold Absolute Pressure Rate Sensitivity None of the enrichments get triggered until the MAP value increases at a rate higher than this setting. ACE4 is how long the variable rate enrichment lasts. So once triggered, you have two different types of enrichment that get added together - a fixed one second enrichment that is currently set to 10%, and a varible enrichment that, as I recall (i.e., double check the manual), starts at your setting (50%) and ramps to zero over the time period you have set (0.5 sec). Quote Link to comment Share on other sites More sharing options...
Hugh Posted May 3, 2006 Author Share Posted May 3, 2006 Ahhh... I misread your post. I will drop ACE 1 to 1.1 see how it does. I did play with that number, making large changes in either direction but couldn't see a change. I will watch it closer now and see what happens. Quote Link to comment Share on other sites More sharing options...
Hugh Posted May 3, 2006 Author Share Posted May 3, 2006 OK, I brought it back to 1.1, and it definitely helped according to this datalog: However, it didn't totally solve the problem. The lag time is still evident, just a little shorter. The car is a little more responsive, but I still get that lean spike. I tried going all the way down with that number, and it still has the lag. Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 3, 2006 Share Posted May 3, 2006 OK' date=' I brought it back to 1.1, and it definitely helped according to this datalog: [img']http://www.zeroyon.com/temp/snapshotdatalog2.jpg[/img] However, it didn't totally solve the problem. The lag time is still evident, just a little shorter. The car is a little more responsive, but I still get that lean spike. I tried going all the way down with that number, and it still has the lag. I read the help again on those settings, and the ACE6 value is added in proportionally to how close to the maximum MAP rate of change the current rate of change is, so you almost never get anything out of it. I think you want to use ACE7 in addition to ACE6. ACE7 is just added in for the time period, without getting scaled by the rate of change. Try 50% in ACE7 and see what happens (might end up being too much...). OR you could try putting a really large value in ACE6, like 250%. Or some combination of the two. Quote Link to comment Share on other sites More sharing options...
Hugh Posted May 3, 2006 Author Share Posted May 3, 2006 As far as I understand the instruction manual, ACE 7 is dependent on the TPS only... It's alright, I came up with a TPS connector that will fit with a little modification. I'll put it on tomorrow and go back to TPS adjustments... this MAP Accel enrich is too much trouble. (and TPS works so well) Thanks a million for the help. I may use some of this MAP stuff in conjunction with the TPS, but will weigh heavily on the TPS. I didn't see anything in the instructions about running the Tec3 without a TPS. It seems as though they expect you to run one all the time, no matter what. The DECEL settings only use TPS as well... Quote Link to comment Share on other sites More sharing options...
TimZ Posted May 4, 2006 Share Posted May 4, 2006 As far as I understand the instruction manual' date=' ACE 7 is dependent on the TPS only... It's alright, I came up with a TPS connector that will fit with a little modification. I'll put it on tomorrow and go back to TPS adjustments... this MAP Accel enrich is too much trouble. (and TPS works so well) Thanks a million for the help. I may use some of this MAP stuff in conjunction with the TPS, but will weigh heavily on the TPS. I didn't see anything in the instructions about running the Tec3 without a TPS. It seems as though they expect you to run one all the time, no matter what. The DECEL settings only use TPS as well...[/quote'] No problem - hope the TPS works out better for you - it is a better way to do acceleration enrichments. I do like to use a bit of MAP enrichment to add some extra fuel when boost starts to hit, since you can't see that on the TPS. Just as an FYI... ACE2, ACE3, ACE4, and ACE7 are all triggered by either TPS or MAP - if either exceeds the threshold you set, these enrichments are triggered. ACE5 is TPS only ACE6 is MAP only ACE8 and ACE9 appear to be TPS only, but they are kind of fuzzy about it. It's a goofy enrichment that I avoid using anyway. Quote Link to comment Share on other sites More sharing options...
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