My 1990.5 allante runs perfect. After driving 15 mins may not start but wants too. Some.popping like not getting fuel. If I'm lucky.can feather gas to get going starting and ots.like.it pressures up.in gas.or clears.out a clogged fuel.line. I just.bought fuel.filter. hey could it be a cat converter?? Help is greatly appreciated. No codes. Ran system. Good battery (will crank over no probs) ran heet water.remover in case bad gas.yes use premium and checked all fuses for furl pump etc. Crank sensor? Please help??