livi1982 0 Posted June 14, 2007 Recently bought a 1.8 16v 1991 Corrado. Car seems to have developed a slight knocking when going into first and second, especially when cold. Is this an indication of a serious problem? Would a fuel additive help? Quote Share this post Link to post Share on other sites
jonnyboyo 0 Posted June 14, 2007 I'm no expert, but try running it on high octane fuel such as shell V-Power, BP Ultimate etc to see if that helps. 1.8 valvers should be run on 98 RON petrol (according to the handbook & petrol flap) not the 95 RON of regular unleaded. Some 1.8's run happy on regular unleaded, but some don't. Give it a whirl though, but make sure you have a near empty tank so its not mixing to much with the regular fuel. Quote Share this post Link to post Share on other sites
