One problem related to other fuel system tank assembly has been reported for the 2018 Audi A4. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2018 Audi A4 based on all problems reported for the 2018 A4.
Engine malfunction prevented the vehicle to engage and a significant lag. Correction of the failure has been attempted twice and a third attempt to correct malfunction is currently in progress with no movement as of yet. Gas tank has been drained and refilled and did not correct issue. Definitely not a gasoline type issue.