Andyweihen Posted June 20, 2020 Report Share Posted June 20, 2020 Okay so Ive tried everything I can and have ran out of knowledge. I let me first give a run down of what is happening. So just finished installing a new turbo, new bosch 980cc injectors and a new NZ wiring trigger kit. So before I did all the work the car had issue where if the air fuel ratio increased above around 12.5 to 1 it would sound like a lean misfire and then the afr would jump around like crazy, I thought this had something to do with the poor low pulse width control on the sard side feed injectors I had on the car, however the problems still seems to be here after ive put the new injectors on. I also had the thought that the timing was completely off with the old cas and it seems weird that the issue is the same with the new trigger kit if timing is the issue. I cant seem to lean it out at idle many more than around 13 to 1 before the afr jump all over the place and the car runs like poop. I dont think its an issue with pulse control on the new injectors as I've seen them used on other cars that have no problem idling at leaner values. I completed a compression test on the car thinking that it might have low compression in one cylinder causing the miss but they all came back over 130psi when warm not full temp so dont think thats the problem. The only other think I can think of mechanically is coilpacks but feel like the problem would be constant and not go away then the car is richened up. Therefore I feel like the tune is completely wrong and Im not talented enough to figure out how to fix it, not sure if its timing related in the tune or what but I have included the cars current tune and a log of it idleing with the issue. Any help would be great I am completely lost on what to do and its the last step before I can finally enjoy the car again. Idle Log 2.pclr Idle log 2.llg Quote Link to comment Share on other sites More sharing options...
Electredge Posted June 20, 2020 Report Share Posted June 20, 2020 if you look at your effective PW... it is quite low between .7 - .9ms you could simply be lower than the injector can function and you are definitely in a non-linear range of any injector. what injectors are you using? and do you have the deadtimes, short pulsewidth adder correct? what fuel pressure are you running? I don't see it in the log so I assume no sensor. you could also add a minimum fuel injector PW and that might fix it, but you might not be able to hit that lean of an AFR at idle. Quote Link to comment Share on other sites More sharing options...
Andyweihen Posted June 21, 2020 Author Report Share Posted June 21, 2020 Ive got bosch 980cc top feed injectors, its running around 43.5 psi base fuel pressure. Ive got the deadtimes and short pulsewidth correct in the ecu not sure if they are the right values to have. It seems the cars idle control also makes the problem worse. I added a minimum pulse width at 0.89ms, that was the lowest value before it started missing and afr was at 11 to 1 which I feel is way to rich to be drivering with. Should I try much lower fuel pressure? Or will it not be able to get as low as I want I do have an adjustable reg. Dead times 10v - 1.689 11v - 1.44 12v - 1.245 13v - 1.100 14v - 0.989 15v - 0.887 Short pulse adder 0.375 - -0.1 0.500 - -0.2 0.625 - -0.2 0.700 - -0.24 0.875 - -0.22 1.000 - -0.2 1.125 - -0.18 1.250 - -0.16 1.375 - -0.14 1.500 - -0.12 1.675 - -0.1 1.750 - -0.08 1.875 - -0.06 2.000 - -0.04 2.125 - -0.02 2.250 - -0.02 Quote Link to comment Share on other sites More sharing options...
Electredge Posted June 21, 2020 Report Share Posted June 21, 2020 2 hours ago, Andyweihen said: Ive got bosch 980cc top feed injectors, its running around 43.5 psi base fuel pressure. Ive got the deadtimes and short pulsewidth correct in the ecu not sure if they are the right values to have. It seems the cars idle control also makes the problem worse. I added a minimum pulse width at 0.89ms, that was the lowest value before it started missing and afr was at 11 to 1 which I feel is way to rich to be drivering with. Should I try much lower fuel pressure? Or will it not be able to get as low as I want I do have an adjustable reg. Dead times 10v - 1.689 11v - 1.44 12v - 1.245 13v - 1.100 14v - 0.989 15v - 0.887 Short pulse adder 0.375 - -0.1 0.500 - -0.2 0.625 - -0.2 0.700 - -0.24 0.875 - -0.22 1.000 - -0.2 1.125 - -0.18 1.250 - -0.16 1.375 - -0.14 1.500 - -0.12 1.675 - -0.1 1.750 - -0.08 1.875 - -0.06 2.000 - -0.04 2.125 - -0.02 2.250 - -0.02 post the current map and let me look at your idle control stuff with the things you have changed... include log if you can Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 21, 2020 Report Share Posted June 21, 2020 I dont see much that would cause your issue in the tune. How sure are you the wideband is reading correctly? Could it be 1 cylinder is leaner than all the others? Is it always the same cylinder than drops out when you lean it out? You could try shifting the injector timing around in steps of about 50 deg and see if it is happier to go leaner with different timing - but it usually doesn't make much difference. Quote Link to comment Share on other sites More sharing options...
Andyweihen Posted June 21, 2020 Author Report Share Posted June 21, 2020 4 hours ago, Electredge said: post the current map and let me look at your idle control stuff with the things you have changed... include log if you can I'll try getting a better log of it running when I get back home in a few days. Heres the tune currently on the car GTST Tune 3.0 - 2.pclr 30 minutes ago, Adamw said: I dont see much that would cause your issue in the tune. How sure are you the wideband is reading correctly? Could it be 1 cylinder is leaner than all the others? Is it always the same cylinder than drops out when you lean it out? You could try shifting the injector timing around in steps of about 50 deg and see if it is happier to go leaner with different timing - but it usually doesn't make much difference. All the plugs look very black and very similar when I pulled them out so dont think one is leaner than the other. I dont think the wideband is reading wrong as the true lambda reading as richer than the as was feel like the ,aster fuel value wouldnt be at 9ms and actually be idling below above lambda 1 as the injectors are larger than the standard ones. Is there anyway I can figure out which cylinder is missing accurately? Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 21, 2020 Report Share Posted June 21, 2020 15 minutes ago, Andyweihen said: I dont think the wideband is reading wrong as the true lambda reading as richer than the as was feel like the ,aster fuel value wouldnt be at 9ms and actually be idling below above lambda 1 as the injectors are larger than the standard ones. Im not sure what you are on about here, but a master fuel of 9 is about normal for 1000cc injectors. But that really means nothing - there are so many other factors all rolled into the master fuel number that you cant use it to gauge whether your wideband is reading correct or not. 19 minutes ago, Andyweihen said: Is there anyway I can figure out which cylinder is missing accurately? Unplug one injector or coil at a time. Quote Link to comment Share on other sites More sharing options...
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