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afr change

Posted: Sun May 05, 2019 12:47 pm
by dluder
Im hoping yall can look at my calibration and datalog to help with issue. My car was running great for the last few months, but since its gotten hotter out my afr has gone crazy. I first tuned it my ait was 90-120 and it ran great. Now im hitting 120-140 ait and afr is really lean at low load and rich med/high load. Normal afr was 13.5 in column 6-7 but when hot its 12.5 Ive tried adjusting ait parameters but its doesnt seem to help.
well as soon as i learn to share calibration and log i will

Re: afr change

Posted: Sun May 05, 2019 9:15 pm
by dluder
Here is my current tune and datalog. please take a look and see if what may be causing afr change. I'll have to record some more datalogs. It gets alot worse if im driving for an hour or more with high ait readings. It always starts off good ait 100-110 14.0-14.2 volts. But as it gets hotter 120-140 ait my voltage drops 13.5-13.6 which is normal from what ive read. Then its almost like an injector is cutting out at low load then its stuck open med/high load. I dont think thats the case but idk its crazy.

Re: afr change

Posted: Sun May 05, 2019 9:32 pm
by dluder
Ha motorsport ecu hondata s300
h22a4
11.1 comp
s2 pro1 cams degreed
stock ported head/intake
bosch 550cc injectors
tri y header catback
cai w vstack

Re: afr change

Posted: Mon May 06, 2019 9:37 am
by Spunkster
Has this been tuned on the dyno? Have you discussed this issue with your tuner?

Re: afr change

Posted: Mon May 06, 2019 11:24 am
by dluder
No tuner or dyno I tuned this myself. I spent a month getting it perfect. But then it just started changing. I had the afr almost perfect but then I started messing with it again due to afr change. I went on a trip a wk ago and it started out good but onece ait got high it was rich across the entire map. TheN it changed lean low load and rich med load.

Re: afr change

Posted: Mon May 06, 2019 11:35 am
by dluder
So far I checked volarge at battery, ecu, injectors, and ran another ground from the thermostat. I've also changed the spark plugs Idk what else to check for I've checked parameter settings and adjusted parameter settings many times. I'll have it good then it'll change hopefully someone has some fresh ideas.

Re: afr change

Posted: Mon May 06, 2019 4:58 pm
by Spunkster
Have you adjusted the compensations for ECT and IAT?

Re: afr change

Posted: Mon May 06, 2019 7:19 pm
by dluder
Yes I sure have but it doesn't seem to help. I've had to take away 7% fuel at 130° ait. Then a wk later I would have to add it back. I had to ad 7% to my low load earlier just to keep it running. It was even lean while driving. I checked my injectors there working good. Idk I'll mess with again tomorrow. I would think it's just a faulty afr gauge but every time it leans out u can definitely feel it. I don't really know what it could be electrical interference, bad ground, ignition, main relay lol idk.

Re: afr change

Posted: Mon May 06, 2019 7:26 pm
by dluder
I am using a real old laptop that lags bad and my afr gauge does go dim sometimes. But it's doNE this since I installed it. It's getting good voltage and I'm grounded to ecu ground. I'm going to try grounding it to firewall or thermostat.

Re: afr change

Posted: Tue May 07, 2019 4:25 pm
by crluver123
I'm guessing you're running the car in open loop at all times?
Getting gas at different gas stations, and different brands, can have more than 5% change in fuel delivery requirements. That's why o2 sensors exist, to compensate for variables like this. Run the car in closed loop, and let the fuel trims do the adjustments for you, AFTER you make sure IAT and ECT compensations are dialed in properly