The Ralliart Fuel Injector upgrade thread.
Sep 16, 2009, 05:36 PM
#16
As far as this miguel all tuning bugs with the FI/C have been worked out. The only thing is as you guys already know anything you change in closed loop the factory ecu is gonna over-ride. But from what I now know we have it a lil easier than you guys as we enter open loop at 40% TPS and you guys don't. And we also have Hackish reflash :bigthumb: for the current time though as Canada is a far drive I think the current best situation would be a hackish basic reflash fine tuned with the FI/C for us in the 4g anyways.
Sep 17, 2009, 06:26 AM
#19
I saw one of his harnesses this past weekend. Very nice in the PnP area since you didn't have to extensively butcher the stock wiring. It included some electronics for the MAF on the eclipse. Not appropriate for the ralliart but still a slick way to do it.
-Michael
-Michael
Sep 18, 2009, 06:05 AM
#21
The ECU's signal processing has several measurement modes and you never know what mode it's in. Unless you can exactly emulate the signal output of the MAF it's nearly impossible to emulate or translate that signal. It might run well at a certain RPM/Load but at a higher RPM it might switch measurement modes. I haven't yet been able to understand the logic behind the modes. I think it's to provide greater resolution at cruise and idle then switch when it needs to measure more airflow, such as mivec and open loop operation.
-Michael
-Michael
Sep 18, 2009, 12:17 PM
#22
The ECU's signal processing has several measurement modes and you never know what mode it's in. Unless you can exactly emulate the signal output of the MAF it's nearly impossible to emulate or translate that signal. It might run well at a certain RPM/Load but at a higher RPM it might switch measurement modes. I haven't yet been able to understand the logic behind the modes. I think it's to provide greater resolution at cruise and idle then switch when it needs to measure more airflow, such as mivec and open loop operation.
-Michael
-Michael
Isn't that what the reflash will do? Change fuel, timing, etc.? The reflash now sounds like the best option. I sent you a PM...
Thanks again,
Carlos
Sep 18, 2009, 03:43 PM
#26
I'm in contact with BrianJ for the harness build, but he needs pics and I can't provide until the next 2 days go by.
If that harness is possible, and the MAF works as it does on the Eclipse, then i see no issue in having the FIC on the RA.
Hackish was telling me about the MAF having different behaviors for different conditions which is what made modifying the signal almost impossible. Let's see what BrianJ comes up with in the next couple of days...
We are WAAYYY out of topic here, aren't we?
Oct 2, 2009, 04:47 AM
#28
The FIC has O2 sensor biasing, and it is well explained in the instructions. Eclipse guys don't use this feature, but I'm kind of fuzzy about needing it for the RA. I did some datalogging with my OBDII scanner and plotted it in a graph to make better sense of the data. About the WOT, I never reached 100% throttle as many people mention here it needs for the open loop condition. My max throttle opening was 85%, I imagine because of my surroundings (87F, not raining, very dry), but I don't know about this. Since the scanner can tell the loop condition(open or closed) I datalogged that as well vs the throttle position.
I gave the loop a 0-1 value so that changes can be seen. The graph shows about 260 seconds of testing, but you can see that WOT for the open loop is not what's happening here. Hackish, I read that other sensors like air temp and coolant temp are taken into account as well, so I will do some testing again with these sensors to compare the changes.
My mods are CAI, header with no cat, stock muffler and rrm underdrive pulley. All of this in an '05 RA manual with an '04 RA ECU.
If you have more detailed data for these conditions, please let me know.
Last edited by cyanide; Oct 2, 2009 at 04:53 AM.
Oct 2, 2009, 08:13 AM
#29
I tried for a few months to get an FIC working. The MAF circuit inside the ECU is different than the eclipse. They have several signal conditioning circuits. One is for low airflows and one is for high airflows. I don't have the schematic in front of me but I seem to remember a third. Each has different signal amplification and this is what makes the system very hard to trick.
You also have a narrow band of adjustment when you go above the stock expectation because the ECU sees the fact you've capped the signal and it tends to throw airflow too high for throttle angle or MAF sensor.
Also, for the O2 sensor manipulation you can't just blindly feed it a signal because the longterm fuel trim will slowly start to skew. Then it exponentially slides in either direction until you start getting system too rich or system too lean. If you look around at turbo kit threads with piggybacks you will see this is a common problem. Car gets tuned perfectly on the dyno, then after 500km it's running massively rich or massively lean.
-Michael
You also have a narrow band of adjustment when you go above the stock expectation because the ECU sees the fact you've capped the signal and it tends to throw airflow too high for throttle angle or MAF sensor.
Also, for the O2 sensor manipulation you can't just blindly feed it a signal because the longterm fuel trim will slowly start to skew. Then it exponentially slides in either direction until you start getting system too rich or system too lean. If you look around at turbo kit threads with piggybacks you will see this is a common problem. Car gets tuned perfectly on the dyno, then after 500km it's running massively rich or massively lean.
-Michael
Oct 3, 2009, 05:43 AM
#30
I tried for a few months to get an FIC working. The MAF circuit inside the ECU is different than the eclipse. They have several signal conditioning circuits. One is for low airflows and one is for high airflows. I don't have the schematic in front of me but I seem to remember a third. Each has different signal amplification and this is what makes the system very hard to trick.
You also have a narrow band of adjustment when you go above the stock expectation because the ECU sees the fact you've capped the signal and it tends to throw airflow too high for throttle angle or MAF sensor.
Also, for the O2 sensor manipulation you can't just blindly feed it a signal because the longterm fuel trim will slowly start to skew. Then it exponentially slides in either direction until you start getting system too rich or system too lean. If you look around at turbo kit threads with piggybacks you will see this is a common problem. Car gets tuned perfectly on the dyno, then after 500km it's running massively rich or massively lean.
-Michael
You also have a narrow band of adjustment when you go above the stock expectation because the ECU sees the fact you've capped the signal and it tends to throw airflow too high for throttle angle or MAF sensor.
Also, for the O2 sensor manipulation you can't just blindly feed it a signal because the longterm fuel trim will slowly start to skew. Then it exponentially slides in either direction until you start getting system too rich or system too lean. If you look around at turbo kit threads with piggybacks you will see this is a common problem. Car gets tuned perfectly on the dyno, then after 500km it's running massively rich or massively lean.
-Michael
Have you read this thread:
https://www.evolutionm.net/forums/04...ml#post7544287
This guy managed to do what you say you couldn't, unless you didn't try using the SAFCII, which uses 0-5v signal modification as does the FIC. Did you try this circuit manipulation for any of the piggybacks you tried on the RA? Locally, I spoke with some RA owners from another town and they say that they have this modification using the SAFC with no issues. I don't like the SAFCII because of its limitations, so that's why I'm looking into other options, but the fact is that they have it working, so I don't see why other piggyback models shouldn't. Also, Haltech has the RA 4G69 as one of the compatible models for their interceptor, but I'm not well informed on this unit. You were working on a Haltech Miniceptor... Did it ever work?
LTFT and STFT will change, as you say, because of the conditions we need for open loop and the fact that nobody's at WOT full time. The ECU will still try learning and managing fuel trims based on your driving. Your reflash feature of open loop on full time sounds good, but I don't see the use if you're not able to tune. If I read correctly, all the reflash does, apart from some of your custom features, is maximize set points on sensors so that the ECU allows for some of the mods like intake, header, exhaust, etc., without trimming fuel, but what about AFR's? Will a reflash keep AFRs where you want them, or will they just run where they do normally, without causing fuel trims for the aftermarket mods?