Electronic Power Control (EPC) idiot light on

[handelaz]

While returing from the Alps of Germany, my 02 GLS 2.0liter (US Spec)while at approx 4800 rpm, auobahns are nice, made a loud thud like when you hit the speedo limiter. The I noticed the EPC idiot light on in the gauge cluster. The manual says take to VW ASAP. My Haynes manual says similar and doesnt cover anything for it either! I was able to drive it home for another 145 miles with it on. There was some power loss while traveling up hills, but the Jetta still went fast like always!
Can anyone help??? Has anyone had similar issues with it?

[Theresias]

Read fault codes, post 'em here. We are not clairvoyant so that we could guess what codes are stored.

[handelaz]

Took it to Gebert VW in Kindsbach this morning and was informed of (2) codes, (1) Mass Airflow Sensor and (2) possible catalitic converter issue. I was assured with a new part (Mass Airflow Sensor) would fix the problem. The only reason the cat convertor was showing up was because the MAS was the 1st fault and when it cleared the cat convertor would clear too!