90' Audi 200 power cuts out when you mash the gas, check engine light appears??

[jerbele]

I have a 90' Audi 200 with auto transmission that has approx $7000-8000 in maintenance the last four years by an Audi tech privately so it has not been neglected by any means. When you mash the gas down on the highway or at about 25mph or higher eventually the power cuts out and the orange check engine light appears?? No vaccum leaks either unless its one the is undetectablly small? From what I've read it mmmight be the throttle switch? I have no idea cause most the reading you find about this car is from the 91' 20v quattro version, so I'm not sure if the same things apply or not. Any suggestions as to what it might be?

thanks,

josh