They told me there were no codes so "there's nothing wrong with a sensor" i know lot about cars, enough to the point that my alternator died in traffic and I was so sure that's what it was that I walked to a local store, bought an alternator and a battery (because I was sure it fried mine) and called a close mechanic to see if he could take me. However, sensors are definitely out of my scope lol. Too many electrical parts. But it doesn't feel like a spark plug. I feel as though something is clogged. Sensor or somethingHave you cleaned your MAF sensor?
Yeah it's pretty bad bucking. My own personal mechanic was like "something is wrong that is absolutely not normal." he could feel the jerking as well. It's more than just a little jump, it's pretty severe where passengers are like swaying back and fourth lolThis seems to be a common occurence with the FB20D. Easier to see with the MT, since we can just WOT the car, and force it to operate in a fixed gear across the entire power band, seeing how the behaviour changes in the 2k-3k range. Same thing is being reported on a 5th gen impreza forum, and noone has been able to pinpoint the problem. Logs seem to indicate a pullback in timing in that RPM range, and the phenomenon tends - allegedly - to be amplified by heatsoak. Mitigation with a higher octane has worked for a few, didn't for others.
I always feel a slight bucking in that range. Easiest to notice it is under WOT in 2nd or 3rd gear, starting at 1000 rpm and flooring it. Just a few days ago (after a 3h trip, engine off, engine on 10 mins later) it was amplified to the point that the car bucked a few times.
Until someone obsessively logs the timing advance and A/F ratio over a few runs, it'll be hard to pinpoint the exact reason.