My 2002 Audi A6 3.0 is ...surging 100-200RPM between like 30 and 55MPH(below 2000rpm)....above that all is smooth. At idle it runs smooth most of the time but every once in awhile surges bad. I checked all the vac lines, didnt see anything bad and cleaned the MAF sensor with no luck. If it was a vac line or something mechanical wouldnt the problem be there all the time? Why intermittent?
Other options/ideas? At this point it does not seam to have thrown a trouble code so I am lost.