I was driving my car last Thursday and had the L shaped coolant hose at the back of the firewall split about a 4 inch length and start spraying coolant. I had no idea what had happened when it occurred, I only saw a small puff of white behind me, and didn't know what was going on. No smell, nothing. So, I took the car the trip home of about 3 miles, and by the time I parked it I glanced at the temp gauge and it was about 2-3 tick marks below the red area. I popped the hood to see that the hose had split, and had sprayed coolant virtually everywhere. Now, fast fore ward to tonight. I finally got the car back together after replacing the hose and doing the required torque check of my ARP head studs after a few heat cycles. I took the car out for a drive and had a severe misfire under any sort of load. I then took the car back home and removed the plug boots to discover that coolant had gotten into the rear 2 plug holes reasonably badly. I sucked the coolant out of all the plug holes and removed all the plugs. They all had faint white markings on the ground straps, but the rear 2 had pretty severe white clean markings on the ground straps. I believe that is a sign of coolant being burned if I remember correctly. I also turned the engine over with the FI fuse removed to push any coolant or crud out of the cylinders that may of gotten in when removing the plugs. I installed new plugs and put everything back together and took the car for another drive. It drives great until I get it into boost. It then has a slight to mild misfire on medium to hard acceleration. Any suggestions on what it may be? I don't believe I blew the head gasket with the metal gasket and ARP studs, at least I hope not.