I was doing a hard pull in 4th gear and suddenly lost power, got power, lost power, let off gas to be safe. felt like a misfire. I thought i had felt this in the past, but this time it is confirmed that something was happening. luckily had obd2 logging on. no misfire or knock codes. data shows the throttle closing from full to closed twice in a row, at the exact time of the problem. i didnt let off the pedal though, so im assuming the ecu detected some condition and closed it. there didnt seem to be a loss of traction and the esp light did not flash.

data at the time this happened:
ignition timing was 10-12 degrees adv. o2 sensor shows a 13.9:1 fuel ratio up until the throttle close. intake air temp 110F. coolant temp 217F. short term fuel trim 15%. running 91 octane (california). dont have a boost guage yet so no info there. MAF readings were in line with the opening and closing of throttle.

mods:
ecu reflash, 18 psi.
apr exhaust manifold. this part made a huge difference. the stock is so restrictive, its a totally different car after installing this-just like ecu flash.
removed mufflers, replaced resonators with magnaflows.
k&n air filter, removed air silencer crap inside air box, otherwise stock intake.
upgraded diverter valve.
recent fuel filter change.
buncha suspension stuff, brakes, not relevant.

can the ecu predict an approaching lean condition before it happens and cycle close the throttle? I have stock injectors, so im thinking they were close to maxed.

 

Yours is drive by wire, when you step on it there might be something wrong with the pedal position sensor or something. See what happens on VAG when you floor it with the car off.

 

I have an older vag (3.11?) that i havent been able to get working... i have another obd2 scanner that is telling me that the throttle is staying open when i floor it. i worked the pedal back and forth throughout the range of motion (car off and on) and the throttle open % seemed to stay right on with where the pedal was. this only seems to happen under a heavy load, and I dont drive my car real hard often so I havent had an opportunity to test it out again. I guess for now its a mystery.

 

the ecu won't close the throttle when it sees a problem... the throttle is an input to the ecu... not an output... the ecm will adjust timing and fuel delivery.

and because you had a reflash it changes everything... even tho your scanner sees the numbers are good... wha a reflash does is change the meaning of those numbers to the ecm

my shot in the dark is tps / throttle control module... just because it reads 4.5v wide open and .5v closed doesn't mean there isn't a dead spot worn on the potentiometer

 

thanks dude, thats something to go on.