P0300 Chevrolet -

Question

03 trailblazer po.300 misfire plugs are fouled with fuel,cat is not clogged

Answer 1

P0300 Random misfire

Check the fuel pressure regulator, it may have rupture and is capable of sending raw fuel into the intake manifold causing the sparkplugs to foul, just pull the vacuum hose off if fuel comes out of the pressure regulator vacuum connection , this is one of the area to check.