When i brought mine(also a 2.0) i thought it could be quicker so changed the MAF and i was amazed at the peformance gain it felt like it had been chipped, it pulls from the moment you start. Only buy proper bosch ones though as ive had lots of warranty returns within one year from an ebay seller with their useless product altough a damn cheaper than the dealers(£35). But yours could have other problems like ignition etc or a fault which would need the ecu to be scanned.