hello everyone
i have a somewhat of a "accel enrichment" issue on some of my tuned cars,(not fuel tip in related)
afr's go lean for a second with small tps increments.
example: while cruising at 4th gear at 8% tps when i slightly open the throttle to lets say 15% afr's go lean for a
second and then goes back to the afrs that i tuned for,
i also know that this is not tip in fuel related since if i change the tip in fuel i am able to get my desired AFR when i
stomp it,

this issue really driving me crazy,
if i look at the logs i dont see a drop in injector duty\fuel value while this happens,

all the cars i'm having this issue on dont have any mechenical problems, no exhaust leaks , good fuel pressure set to
43 psi with vac line off, no battery issues, no electrical issues,


i tune all my cars with neptune #bestsoftwareever (since im a dealer) on open loop, ve tables disabled, and the rest of the settings in the open loop folder are default
ignition adjustments enabled and ignition limitations disabled.
tip in ignition is set to default
here is a short video of the issue in real time,

i will post datalog screenshots the datalog file and one of the maps but for now here a 3 videos from 2 different cars
showing my issue


thanks alot, any advice will be welcomed, please turn the subtitles on so you could know what i'm saying



thanks

 

I'm going to go ahead and say I'm not familiar with NepTune, so I don't know if you have this setting, but are your injector deadtimes set correctly?

 

I had this issue really bad in the past, so bad it would fall on its face with sharp changes in tps. It ended up being my injectors (they were random cheap ones off eBay lol), the issue went away when I upgraded to in900cc ev14 style injectors. Like 80% said make sure your injector battery offsets are correct for the injectors AND fuel pressure you're running. The most important thing is that you are getting the right amount of fuel when you stomp on the gas.

 

^^^ Agree with that. Best thing to do would be to check fuel trims and make adjustments by adjusting injector scaling and battery offsets. Make sure the fuel trims are as close to zero as possible and then retune.

 

thanks for the replys everyone,i have this issue on 2 cars,
my offsets are correct,
one with stock injectors and stock injector offset,
for the second car i'm using rc750s with the offsets supplied by he sofrware and i also tried the facrory supplyed offsets by rc, i had to make a new map ofcourse but i didnt see any difference,

my fuel pressure is good, system holding pressure with engine off so i know the regulator is ok and the pressure release valve inside the pump is good,
, and pressure is set to 43psi with the vac line off, also there is no drop in pressure while this happens,
thanks

 

I think you will be fine as long as you can get the proper fueling when you stomp on the gas, although annoying this is probably one of those things you have to live with when using a 25 year old ecu. When I tuned my old 2004 wrx with the stock ecu using rom raider & ecu flash there was a whole 2d table for tps tip in enrichment based on throttle position and % of fuel added. That would be pretty handy in this case for you as you find the limitations of a single overall tip in trim for all throttle positions. I do like like how simple Neptune rtp makes things, but it is really nice to tune newer stuff with more options too.

 

thanks,
one of the cars in the video (the one with the rc750's idles perfect at 14.7afr with the overall fuel trim set to 0,)

 

yeah sure its an old ecu, but other cars of mine dont have this issue, and i never had this issue in the past,
although im using neptune on these cars, i tried also crome on them and had the same results.

 

Have you checked your MAP sensor and/or TPS?