Hey, i looked it up in the Service manual and it could be a number of things...
Malfunction in ECU, Malfunction in mass airflow sensor, Malfunction in engine coolant temp sensor, Malfunction in Vehicle speed sensor, Malfunction in ignition signal curcuit, Malfunction in overheat self diagnosis, Malfunction in heated O2 sensor, Malfunction in throttle position, Malfunction in Turbo pressure sensor.....
So as you can see it could be a lot of things..... in the service manual it shows you what you can do to diagnose these.....
I got my Service manual from HERE You just need to register to download it
Hope this helps a little
Mr Sniper911