I have a 2009 Jetta (140K miles), when I first turn on the engine, the engine runs rough and rpm is high, but after a few minutes it is smooth again (rpm at normal idle). Any suggestions on where to start.
High RPMs are normal right after a cold start–depending on how high the RPMs.
What is the reading on your tachometer when the engine is revving “high”?
Is the Check Engine Light on when the engine is running roughly?
No check engine light, no codes. Oil level is OK.
I edited my original response to add a question, and I think that this was prior to your last post:
When were the plugs changed, and if they were, are the new ones recommended by VW?