R32GT-R Posted April 13, 2007 Share Posted April 13, 2007 (edited) Car 1989 GTR PFC,Z32 AFM's,800cc Sard Injectors,Boost kit, Trust t618z turbos, big IC etc.... My car is set up correctly with correct injector settings for the PFC and my 800's no leaks in intake system, pressure tested it, no stuck injectors. o2 feedback turned off I have checked all my sensors, MAFs are 1.1v @ idle Vacume -630 milli bar @ idle is dead on, FPR @ idle is dead on 36 PSI hose on, 43 PSI hose off. Coolent temp is good Air temp is good TPS .5v & Idle switch on @ 0% TPS My car runs excessivly rich at idle 10:1 AFR, no amount of adjusting the INJ map will bring it up past 13:1 AFR and even at that 13 afr the map must be adjusted to ask for a 29:1 AFR. I have adjusted the AirFuel offset from 100% to 40% to bring it up to stoich but after some reading this is not what that adjustment is meant for. from what i gather it is meant for quick observations of load and the relation of mixtures. so to permanantly leave this vale @ 40% is unacceptable to me. I am leaning towards it being a vacume issue. I capped all the unused pipes when i removed the carbon cannister(EVAP) as well as capping the unused pipes from the factory boost solonoid as well as a couple other which i found under the plenum. I am thinking maybe that their was sposed to be a open to atmos pipe to regulate mixtures at idle. can anyone confirm this. BTW Car idles fine, great actually its just overly Rich. I have been scratching my head on this for several weeks any help would be greatly appreciated. Edited April 13, 2007 by R32GT-R Link to comment https://www.sau.com.au/forums/topic/164368-overfueling-idle-pfc-help-please/ Share on other sites More sharing options...
seeyagtr Posted April 13, 2007 Share Posted April 13, 2007 Mmmm, The other item to check will the fuel pressure reg..... should drop fuel presure down, there for reducing the amount of fuel through injectors Turn your O2 feed back and control on...... Takes care of it for you.. Link to comment https://www.sau.com.au/forums/topic/164368-overfueling-idle-pfc-help-please/#findComment-3046813 Share on other sites More sharing options...
blind_elk Posted April 13, 2007 Share Posted April 13, 2007 Can I suggest that with 800cc injectors, you are NEVER going to attain a clean idle. The injector open time will be so short that you will not get a good spray pattern, and even at a minimum opening time you will simply dump fuel into the engine. And a 13 AFR is not really all that bad (certainly better than 10!) Link to comment https://www.sau.com.au/forums/topic/164368-overfueling-idle-pfc-help-please/#findComment-3046821 Share on other sites More sharing options...
R32GT-R Posted April 14, 2007 Author Share Posted April 14, 2007 Can I suggest that with 800cc injectors, you are NEVER going to attain a clean idle. The injector open time will be so short that you will not get a good spray pattern, and even at a minimum opening time you will simply dump fuel into the engine.And a 13 AFR is not really all that bad (certainly better than 10!) 1000's can idle at stoic so my 800s should have no problem. @ idle my injector % is 1.5 so i can drop more then it is allowing me. my FPR is good as well any other ideas? Link to comment https://www.sau.com.au/forums/topic/164368-overfueling-idle-pfc-help-please/#findComment-3048843 Share on other sites More sharing options...
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