I have a problem with my car running rough,feels like it is skipping,especially at higher speeds.From a dead stop or when moving slowly if you get on the gas hard the rpm`s run up and hit the rev. limiter.You can also see some smoke come out of the exhaust and also some soot collects on the bumper over time.Can anyone give me some help on this problem?Also usually when the car starts to run rough the check engine light comes on but goes back off after a while.Any help would be greatly appreciated.

with the soot build up it sounds like you have a mixture problem but i am not up on the new electronics/fuel injection stuff but it does sound like its going to be a sensor in the fuel injection.

Get it scanned for the code. My guess is something regarding emissions is bad or going bad (intermittent). Probably an O2 sensor(s). Start with a scan and let us know what code(s) you are getting. Ed