I monitor my OBDII port with an Ultragauge. I would NEVER advise someone to go to a dealer with a Crossfire, unless they can find a Mercedes dealer that will look at it.
What makes you think a check engine light is an automatic trip to the dealer? That is the LAST place you go - and after you have been around here a while, you will know why!


JJ- get yourself an Ultragauge ($80) and plug it in and wait, or, the next time it acts up, take it to AutoZone or Advance Auto and have the code(s) read - then come back here and we'll see what we can do to help.