I am having a problem with my sons 1998 Golf. It fires up no problem. If you put it into drive and let your foot off the brake it rolls forwards. Change to reverse and it rolls backwards but as soon as you step on the gas to drive it it dies.I have replaced the fuel filter and vacuum hoses to the fuel pressure regulator, also the supply and return fuel hoses that attach to the fuel pressure regulator with no difference. Any hints or advice are greatly appreciated.