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I think the key to getting idle that low is really a balance of the mechanical settings of the TB (idle bleed, plate set screw, TPS table choke) and proper use of the ISC valve. Its pretty easy to balance out with a stock or street port, but as port size increases so does sensitivity of that balance. What does the car idle at if you close the bleed screw all the way now?
Skeese
Havn't tried yet. Wife has had me doing other **** right now. Which one are you calling the bleed screw? I'm going to play some today or tomorrow.
Havn't tried yet. Wife has had me doing other **** right now. Which one are you calling the bleed screw? I'm going to play some today or tomorrow.
Carl
Yeah man I understand that...
The bleed screw I'm refereing to is the one on the bottom of the TB that is below the primary throttle plate. There's a small inlet hole in the primary tb inlet that allows air to be pulled to the engine side of the TB and that bleed screw position regulates how much. Fully closed all the way clockwise nets no air bypass and lower idle rpm and opening by turning counter clockwise allows more air and higher rpm.
The one on the top is the mechanical stop for the TB plates at whatever 0% throttle is. Anytime you change this you have to recalibrate TPS, but that isnt the case with the bleed screw.
I always tune idle to where I want it to be in open loop idle control and then run closed loop later. That being the case, for your car I would try and lower the idle rpm from 900 to 800 by closing the bleed screw some (assuming it isnt fully closed already, if so theres a fix for that too) and leave the ISC duty as it is. Set the ISC duty bump for the low rpms ( I forget what its called) to bump by 20 at 750 rpms and 50 at 700 rpms to help catch it if it falls off.
With my stock port that idled at 800 rpms, I added fuel in the 500 rpm cells to aid it catching if it fell. Will post a pic of the fuel map to show it when I can.
Ya that's what i thought. I know it by a different name. But i just dropped the car at a body shop as one dick head hit me in a parking lot. Lucky it's not bad. But getting her cleaned up. So it'll be 2 weeks or so. I'll mess with the idle after i get her back. But i did have to add more timing to the idle. so sitting at 15 and she doesn't stall out at all now. also idle afr she likes 12.2. so I don't think i'll lean her out any more.
But your right it is easier getting the fuel dialed in in the 500 rpm steps. One thing i have noticed is that she wants a lot more fuel in the 2500-3500 rpm range. around -16. my -12 table seems to be almost dead on. just seems weird to me to see the -16 cell wants more fuel than the -12 cell.
Ya that's what i thought. I know it by a different name. But i just dropped the car at a body shop as one dick head hit me in a parking lot. Lucky it's not bad. But getting her cleaned up. So it'll be 2 weeks or so. I'll mess with the idle after i get her back. But i did have to add more timing to the idle. so sitting at 15 and she doesn't stall out at all now. also idle afr she likes 12.2. so I don't think i'll lean her out any more.
But your right it is easier getting the fuel dialed in in the 500 rpm steps. One thing i have noticed is that she wants a lot more fuel in the 2500-3500 rpm range. around -16. my -12 table seems to be almost dead on. just seems weird to me to see the -16 cell wants more fuel than the -12 cell.
My engine is also street ported but she brapps very well at 800 rpm with 0 base timing which equates to -5 to 0 timing at idle. I believe factory timing is -5. For spark split I have it at 20 for 0% and 25% tps at 1000rpm and the rest is at 10. If you change the spark split it does influence idle a bit. I believe 15 is stock but I can recall reading that 20 helped a few people with ported engines idle better. I opted to give it a try and found it helped even if it was just a small amount. I highly recommend doing most of the steps I mentioned in my previous post to get your idle on lock. I know most cars are different but I think your car will be better off with a rich idle in the 12s. If you keep it at 13 you will need more timing and/or a higher RPM to keep the engine from stalling when load is applied at idle, this includes clutch applied load during first gear take off. You can add timing in the lower RPM range to help support the engine from dying but at target idle I think its best to stay as close to factory as possible. Key points I strongly believe to setup idle appropriately are: lock idle timing to -5/15 via ecu or jumper, double check timing marks, manually adjust TB to target idle RPM, tune in open loop with ISC off idle fuel map to a target afr of 12-12.5, readjust TB back to target idle RPM manually if fuel map tuning resulted in a rise/drop in RPM, turn ISC back on, and then work on transient throttle. You posted in my megalogviewer thread, refer back to that to help fill in your predicted map and begin tuning your transient throttle. I made a few more tweaks afterwards to get it just right but feel free to PM me if you have any questions. That feeling I got when I finally got my idle and transient throttles solid was just exhilarating with a complete sense of accomplishment. If I can, I would like to share with you that sense of satisfaction.
My engine is also street ported but she brapps very well at 800 rpm with 0 base timing which equates to -5 to 0 timing at idle. I believe factory timing is -5. For spark split I have it at 20 for 0% and 25% tps at 1000rpm and the rest is at 10. If you change the spark split it does influence idle a bit. I believe 15 is stock but I can recall reading that 20 helped a few people with ported engines idle better. I opted to give it a try and found it helped even if it was just a small amount. I highly recommend doing most of the steps I mentioned in my previous post to get your idle on lock. I know most cars are different but I think your car will be better off with a rich idle in the 12s. If you keep it at 13 you will need more timing and/or a higher RPM to keep the engine from stalling when load is applied at idle, this includes clutch applied load during first gear take off. You can add timing in the lower RPM range to help support the engine from dying but at target idle I think its best to stay as close to factory as possible. Key points I strongly believe to setup idle appropriately are: lock idle timing to -5/15 via ecu or jumper, double check timing marks, manually adjust TB to target idle RPM, tune in open loop with ISC off idle fuel map to a target afr of 12-12.5, readjust TB back to target idle RPM manually if fuel map tuning resulted in a rise/drop in RPM, turn ISC back on, and then work on transient throttle. You posted in my megalogviewer thread, refer back to that to help fill in your predicted map and begin tuning your transient throttle. I made a few more tweaks afterwards to get it just right but feel free to PM me if you have any questions. That feeling I got when I finally got my idle and transient throttles solid was just exhilarating with a complete sense of accomplishment. If I can, I would like to share with you that sense of satisfaction.
-groovin
Thanks ya i'm going to go threw those steps just waiting on getting the car back. Hopefully sometime next week.
Got the car back friday. I put my headlight covers on finally but need to adjust them some.
Think i have the idle as close to 800 as i can get. Here is a log and the ecu settings. But ya was just a little off in the timing. She didn't stall at all during the log run. I think i may have found my culprit also as to why the idle was kicking in. I have my SSI-4plus in the same pocket as the ecu. I moved it out and it's sitting on the passenger floor pan right now. I'll drive her this week to see if that is what was causing the issue. If so I'll rewire it and move it to a location a little farther away.
Thanks to groovin I now have my idle at 800 rpm's! Sounds really damn good too! I'll try and get a video of her running and post it in here. 12.2 afr, timing is at 0 for 500 and 1000 rpm and split is at 20 for both 0 and 25 @1000. I added a quick log to show and the ecu file. Moving on to more fuel tuning and get the Predicted MAP table better off. But i think that is pretty close.
Towards the end of the log I turned everything on, Lights, held the break down, rear defroster, heater and radio. Looks like she was holding 850ish and didn't stall out. So I think we are good but gonna do some driving soon and test more than just in the driveway.
Thanks to groovin I now have my idle at 800 rpm's! Sounds really damn good too! I'll try and get a video of her running and post it in here. 12.2 afr, timing is at 0 for 500 and 1000 rpm and split is at 20 for both 0 and 25 @1000. I added a quick log to show and the ecu file. Moving on to more fuel tuning and get the Predicted MAP table better off. But i think that is pretty close.
Towards the end of the log I turned everything on, Lights, held the break down, rear defroster, heater and radio. Looks like she was holding 850ish and didn't stall out. So I think we are good but gonna do some driving soon and test more than just in the driveway.
Carl
I am very happy to hear that it worked out well. Now with your timing back to 0 at idle your closed loop ignition can work properly under load if assistance is needed. If you have a/c or an electric fan don't forget to fill in the extra effort table. The more accurate your extra effort number is the smoother your idle will be during load transitions.
Transient throttle should be next. Refer to my megalogviewer predicted map thread that you posted on for guidance. This will require a bit more trial and error but you should be able to get a solid baseline in neutral just stabbing the throttle and listening to the motor respond. I noticed most people tend to have a transition time between 100-300 ms. In my case I used 100ms and my vacuum source was the UIM using the port closest to the firewall next to the passenger strut tower. Transition time is influenced by vacuum/boost line length that goes from the engine to the internal map sensor on the ecu. Depending on vacuum/boost source location you may also have a lot of artifact so most tend to activate kpa filter > 70 but I think the ECU defaults with it on? I noticed my car preferred a pretty high asynch gain % (pretty much maxed out on adaptronic series 6 pnp ecu). With double asynch checked my aysnch gain % was set at 250. For extra cold I think the recommendation is about half the value your asynch gain is but to get it dialed in you'll have to test it when your engine is cold. I noticed a value between 5 and 8 for persistence worked best. For added smoothness and additional support on take off add a bit of advance timing during transient throttle. consider maybe a 2.5 with a max of 5. Again these numbers were based on lots of trial and error with my engine setup but I think the basis should roughly hold true for you as well.
Keep us posted as usual and glad everything is working out so far.
Before we move into transient throttle, do you have any logs from the latest fuel map outside of idle? I never saw any drive/cruise/boost log data since I revised the whole map. Would just like to take a look at an open loop log that covers all driving conditions to make sure base fuel is squared away before you start putting too much stock in sorting transients.
Skeese I think I may have a grounding issue but not sure. I read threw this old forum post https://www.rx7club.com/3rd-generati...re-kit-599348/ Might give that a go and make some more ground connections. Here is a run i did yesterday taking my daughter to collage. Fairly short but gets you an idea at least.
Skeese I think I may have a grounding issue but not sure. I read threw this old forum post https://www.rx7club.com/3rd-generati...re-kit-599348/ Might give that a go and make some more ground connections. Here is a run i did yesterday taking my daughter to collage. Fairly short but gets you an idea at least.
If your able to drive the car then I think your base map is fine. I recommend setting fuel to open loop, setting spark to open loop, turning off throttle over run, make sure your target afr are where you want, make sure your wideband is working properly and then datalog for 30-45min while driving the streets/highways doing so with light throttle only trying to cover as many cells as possible between 0-101kpa at most. Then use that datalog to setup your transient predicted map. Feel free to use guesstimates for unknown areas or leave it as is from the base map. You can then use that same datalog to begin tuning your VE map. Skeese has a good writeup using megalogviewer to tune VE. Follow his guide for that. After making your adjustments I would repeat this a few more times just to make sure everything is in order and your VE map from 0-101kpa is within 1-2% of your target afr. 1-2%. Your datalog will vary based on temp, altitude, and humidity so as much as possible try to keep your route, season, and time of day the same to minimize any variables that would skew your data. After you get daily driving down then you can start working on the boosted areas starting in small increments. Skeese covers this well in his guide. Once your done with all your boosted cells and finish tuning at WOT you can turn on closed loop for fuel. Some people prefer running open loop for WOT. There is a box you can check to do just that if you want. If you stay in the same area that is probably the safest path to take but if you plan to go WOT at different locations you may want to leave closed loop on and make sure your wideband is always working properly. As your working the boosted sections you can also use those datalogs to fill in the predicted map.
The car was tuned for the 99 turbos a while back in 2014, rebuilt the engine and did a bunch of stuff to the car. Was tuned for 14 psi and laid down 350ish to the wheels. But even then I had issues with the tune. Since then I added the efr 8374 in late 2016. But it just seems like the afr stays the same even thou i added or removed fuel in some cells it seems like it's just not enough fuel example the -16 to -28 cells at 3000 RPM.
It has started raining up here but looks like I'll have some dry weather this weekend. I'm gonna add some grounds as from when I looked yesterday all i have is a few stock ones. I have read a lot of issues can be caused by poor grounding so may as well make sure it's solid. So let me ask this question, where should my MTX-l be grounded?I read in the man that they recommend it be attached to the battery for the - (neg) but it isn't, it's grounded to the chassis. I also want to look to see how the ecu is grounded since this is a PNP model of the ecu. I'm wondering if I can add a ground to the ecu to make it better. then maybe the idle will stop kicking up randomly. The shop that did the car did all the work and I find myself fixing a lot of there **** work.
I did do a little bit of playing and the throttle response seems really good right now i'll refine it some more but so far it's very responsive.
Transisition time 100, Asynch gain 175, extra cold 100, persistence 2.
The car was tuned for the 99 turbos a while back in 2014, rebuilt the engine and did a bunch of stuff to the car. Was tuned for 14 psi and laid down 350ish to the wheels. But even then I had issues with the tune. Since then I added the efr 8374 in late 2016. But it just seems like the afr stays the same even thou i added or removed fuel in some cells it seems like it's just not enough fuel example the -16 to -28 cells at 3000 RPM.
It has started raining up here but looks like I'll have some dry weather this weekend. I'm gonna add some grounds as from when I looked yesterday all i have is a few stock ones. I have read a lot of issues can be caused by poor grounding so may as well make sure it's solid. So let me ask this question, where should my MTX-l be grounded?I read in the man that they recommend it be attached to the battery for the - (neg) but it isn't, it's grounded to the chassis. I also want to look to see how the ecu is grounded since this is a PNP model of the ecu. I'm wondering if I can add a ground to the ecu to make it better. then maybe the idle will stop kicking up randomly. The shop that did the car did all the work and I find myself fixing a lot of there **** work.
I did do a little bit of playing and the throttle response seems really good right now i'll refine it some more but so far it's very responsive.
Transisition time 100, Asynch gain 175, extra cold 100, persistence 2.
Carl
Grounding to the chassis is fine but make sure there is solid contact with the chassis and don't stack multiple grounds at one point. Grind the surface of the location you plan on using to expose the metal body then use a nice metal washer or o-ring terminal. You can even add a tiny bit of carbon conductive paste. Ideally, sensitive sensors like widebands and ecus should be grounded separately. Also make sure your battery terminal ground isn't loose, dirty, or oxidized. As well as the point where it is grounded to the chassis. I would add a secondary grounding point from the terminal to the chassis while your at it.
Try setting your setting extra effort in the idle tab under open loop idle control a bit lower on your electrical loads and see if that doesn't help with the idles randomly spiking. Consider cleaning the iac valve. Many times carbon builds up and prevents it from operating smoothly. Unplug it, take it out and clean it as thoroughly as possible and put it back in.
I dont know much about fd rx7s. But i had grounding issue with adaptronic 440d select with aem smart coils. All because i had it grounded to the body of the car. Star ground on the engine is what fixed my erratic electrical problems with my MTX-L. Its how all oem do it. Last paragraph sums it up pretty good on this link. https://blog.turbosource.com/2017/02/01/ecu-grounding-do-s-dont-s-by-adaptronic/
@holdfast. ya i did a few grounds. But it seems that isn't helping either. I'm prob going to pull the ICV and have a look/clean it or see if I can get another one. I honestly don't know what is causing the idle to randomly spike the way it does.
@skeese Here is a log yesterday. I took my son to his soccer game 30-40 min drive. I had to use winrar to compress it. log file was too big for the forum.
Been a while for an update.... So grounding did not help with the iac issue. But I do have a solid 14-13.8v. It seems it may be the ECU. I have a friend close by going to let me borrow his ECU which he isn't using right now. Same one i have the old Adpatronic PNP. but in the logs it shows a ZERO "0" RPM for a split second and the idle jumps right up. I put a new ticket in with Adaptronic so we'll see what they say. So going to try the ecu and see if it works. If not I'll pull the cables to the iac and run new cables in case that is the issue. I'll be installing water inj this weekend. Long time over due honestly.
Yeah, the datalog opened in Excel shows only 1 row where the RPM drops to 0. Then the ECO responds as if it just started up and increases idle effort to 100.
When you are experiencing the RPM momentarily going to 0. The ECU momentarily goes back to cranking mode then recalculates the post crank idle and post crank fuel trims. Now if you want to borrow an RX7 Select plug-in ECU to test, I don't think we have them available in Sydney anymore. You can try to talk to Elliot, since you are in US as well. Apart from the ECU, this could also be caused by a faulty crank sensor. Another thing to try to further narrow the problem down is to change the CAS input from CAS1 to CAS2 and see if it happens. The ECU file would have to be changed for trigger settings as well of course.
So it looks like i need to switch pins 2e (cas1) and 2g (cas2) and change the settings in the ecu to see if it still occurs..
ya same.. I'm headed to my friends today to swap ecu's... His is unused. I wanna see with his if the fuel table will want to be changed also in those cruise cells. Will tell me right then and there my ecu would be going to ****....
So Confirmed. My ECU **** itself... Updated my friends firmware, added my ecu file and dropped it in the car. Had it in for close to an hour. The idle never jumped and we also took it for a drive. Those cruse cells that are insanely high i have been wondering about.. in his ecu i had a trim of -4 to -14 from idle in threw the cruse cells. So the cas1 and the inj drivers are bad or going bad. I just finished emailing Adaptronic support also.. So we'll see what they say. My only issue is it's out of warranty so i may be screwed...
So Confirmed. My ECU **** itself... Updated my friends firmware, added my ecu file and dropped it in the car. Had it in for close to an hour. The idle never jumped and we also took it for a drive. Those cruse cells that are insanely high i have been wondering about.. in his ecu i had a trim of -4 to -14 from idle in threw the cruse cells. So the cas1 and the inj drivers are bad or going bad. I just finished emailing Adaptronic support also.. So we'll see what they say. My only issue is it's out of warranty so i may be screwed...
Carl
Damn, sorry to hear that man. Adaptronic suckage strikes again.
Now I need to save up again to get a new ecu. Need to find what will work with the stock harness or if i should just replace the whole thing....
Carl
You can use a haltech elite with any of the FD RX7 patch harnesses from the E11 forward to get from the universal ECU to the factory harness. I ran my both a ps1000 and my current haltech elite through one without any issues. I think they go for ~$200.
09-22-18, 05:54 PM
