ECUflash shuttering at 2k rpm in low load light throttle

[jakeachy]

Got back into these, and put in a flash ecu recently.

I tuned it well on corn today, beat the piss out of it and it was great.

I let it sit for 4 hours, and now it shudders like it is missing at least one cylinder right at 2k onwards with light throttle and low load. I go from 14.4 to 18:1 with the shuttering, making me think an injector or spark issue?
BUT, WOT, it is very quick and flawless. Shift up and let off, and it goes bad.

I'm thinking I may have fouled a plug? Come to think of it, Ididn't regap the plugs lower for the corn. Coming from the Subaru world, that isn't usually required.

Note my fuel trim in use is 8% off its fuel trim low. Do I have to reset the ecu when changing latencies for cruising? Also, the o2 feedback goes to 0 when it shudders..

Well the plugs look good, and of course evoscan is junk and won't display any codes...

Perhaps my tps sensor is causing this? I can't get it to go lower than the 12%

Reset the ecu and the problem went away. I'm assuming the difference in stft and ft in use caused it

 

[Black95TSIawd]

12% for the tps is fine. I would log load as well to understand where you are running in your timing and fuel maps or if there are any errors. Also, plugs are cheap. Throw in a whole new set and see how long they last.

 

[jakeachy]

well, this happens again. this time, with a fresh 6 bolt.

when i am in low load, low throttle, the car will cut out on what seems like one cylinder. it will go to 20:1, which makes me think its just one stuttering.

Do these ecus do something when the fuel trims are locked at 12.5? I have smoothed my maf to add some fuel at 60hz, but it doesnt take it away. perhaps i have a boost leak.

my other idea is that my junky ptes are failing..