I know this problem been discussed many times before, i was reading all over online we still couldnt get a fix, i honestly dont even know if there is..
A friend of mine have a 2003 CTS, he keeps getting the error "Reduced Engine Power". When this happens the gas pedal becomes useless, and the car would come to a stop till he scans and clears

he scanned it and he keeps getting the following codes:
P2119
P0700
P2176
P1779
P1795

when he clears them, the car runs better than it ran the day they made it

he went to few local mechanics and to Cadillac itself more than once, he was biased few times and told to change the following, which he did but it didnt fix the problem...

front O2 sensor
rear O2 sensor
spark plugs and wires
cleaned the MAF and throttle body

going to the dealer is becoming very expensive, he finally decided to ask around..
any suggestions and help is greatly appreciated

thank you
Sammy