cabletie Posted November 20, 2021 Report Share Posted November 20, 2021 Hello everyone. I'm experiencing a new problem on our costumer car with g4+ evo 8. I went on the dyno and all went good. I did one map with pump fuel and then I did a separate map for E85 using that previous map as a starting point. After a trackday with the car I personally made a long trip back home with the car, I had some ethanol left in the tank but I refueled with pump gas on the way back. After a while I did a 3rd gear pull and i had a lean condition. From that point on, (I've also uploaded back on the first map I did on the dyno with pump fuel) I have a lean condition at 0.6 bar of boost. Today I checked all the fuel system (pumps, lines, filters, FP regulator) and I've also fitted a FP sensor to log pressure without luck. I have no idea what's going on. I tried to put 11 AFR as a Stoich value on the fuel main and magic, the car was rich but no lean condition anymore. What am I missing? here are some logs and map Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 20, 2021 Report Share Posted November 20, 2021 No log or tune attached. Quote Link to comment Share on other sites More sharing options...
cabletie Posted November 20, 2021 Author Report Share Posted November 20, 2021 sorry Adam. Here they are evolean.llg mappa100rama_leanprotection.pclr Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 20, 2021 Report Share Posted November 20, 2021 Nothing obvious jumps out at me in that log. Does it run lean on ethanol too? The injector PW is larger than I expect so it suggests there is a lack of fuel flow as the high VE suggests. Can you attach the map that has the fuel press sensor set up so I can confirm that. Do you have any old logs of it running ok on pump gas? I'd probably check injectors too if nothing else comes up, we used to see lots of issues with the 2200 injectors coming back with really restricted flow at my last job. Quote Link to comment Share on other sites More sharing options...
cabletie Posted November 21, 2021 Author Report Share Posted November 21, 2021 Here is the map with fuel sensor calibrated. If you open the last log with this map, you can see fuel pressure as well. The other log was on meth but had 4D fuel corrections, but It shoud give you the idea I think. On ethanol it runs good. The other strange thing to me is that if I change the stoich on the fuel main to a richer value ( I tried 11 AFR just to try) It was rich but was working. I will inspect injectors for sure at this point,I have no other ideas at the moment. Thank you Adam mappa100_idleignition_fuelsensor_newstartup.pclr 100-200_6.4.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 21, 2021 Report Share Posted November 21, 2021 What fuel pressure sensor do you have? That doesnt look like a realistic calibration for any of the common pressure sensors I have come across? 19 hours ago, cabletie said: The other strange thing to me is that if I change the stoich on the fuel main to a richer value ( I tried 11 AFR just to try) It was rich but was working. That is expected, this will just make the ecu add proportionally more fuel. The question we need to answer is why is the fuel system flowing less fuel than the ECU is calculating. It looks like the log from "runs good on ethanol" was from before the problem occurred as there is no differential fuel pressure compensation set up in that log. Quote Link to comment Share on other sites More sharing options...
cabletie Posted November 22, 2021 Author Report Share Posted November 22, 2021 It is a no brand pressure sensor, 0-150 psi range. I used the preset scale in the menu and then offset a bit, to match actual FP with another gauge attached to FRP. the last log I attached yes was before the issue. I have no recent logs on Ethanol, I need to change fuel and do that. I found that in my injector setup on pump fuel the injector flow is 2235cc as stated on FIC paper, while on my E85 calibration the injector flow is 2150cc. That's for sure my error but could that be the reason for working on ethanol? Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 22, 2021 Report Share Posted November 22, 2021 19 minutes ago, cabletie said: the last log I attached was on pump gas and yes was before the issue. In the log 100-200_6.4.llg it shows ethanol content was 69% though? 21 minutes ago, cabletie said: I found that in my injector setup on pump fuel the injector flow is 2235cc as stated on FIC paper, while on my E85 calibration the injector flow is 2150cc. That's for sure my error but could that be the reason for working on ethanol? Whether intentional or not I dont know, but its probably fairly realistic, they do generally flow 7-15% less when tested with ethanol. As for the fuel pressure cal, I dont think it would be wrong enough to cause the issue, but im still not convinced it is correct, it should be 0kpa at 0.5V. Unless maybe it is an absolute sensor rather than gauge pressure? Im still most suspicious of the injectors at this point. Quote Link to comment Share on other sites More sharing options...
cabletie Posted November 22, 2021 Author Report Share Posted November 22, 2021 yes it was 69% because there was some pump gas left in the tank. I will open and clean injectors at this point today and let you know. Thank for help Quote Link to comment Share on other sites More sharing options...
cabletie Posted November 22, 2021 Author Report Share Posted November 22, 2021 so to update, injectors were super clean. I worked around it by now setting the actual flow to 2150cc instead of the 2235cc that was on the FIC sheet, and made small adjustments, I will try with e85 again and log. All the fuel system is pretty new so there should be something else... Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 22, 2021 Report Share Posted November 22, 2021 You really need to flow test the injectors, I wasnt too worried about cleanliness - although they also prone to blockage since they dont have baskets in them, the main problem with the 2200 injectors is they were designed for CNG so have plastic internal components that can swell up reduce flow, it usually seems to happen worst when changing between fuels. I have seen some old ones that have reduced to as far as 1700cc. Quote Link to comment Share on other sites More sharing options...
Daniel B Posted January 20, 2023 Report Share Posted January 20, 2023 Hey cabletie. Did you manage to find the issue? I'm having similar issues also Thanks Quote Link to comment Share on other sites More sharing options...
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