4.6 2v misfire

Need help diagnosing whats wrong with my 03. No shop in my area (south FL) will touch the car because its “too old”. All new top end (original cylinder heads failed leak down test and had bad spark plug repairs). Here is what has been changed…ported stock 99 casting heads with SI valves...

Hello, I have a 1998 Mustang GT that has a vortech V1 with FMU. I bought the car 2 years ago (mods were already on the car) and did a bunch of maintenance at that time. 10w30 mobil 1 synthetic with FL1A New coolant New brake fluid New PS fluid New trans fluid New rear diff fluid New fuel...

Had a CEL on for misfire cyl 4. Replaced all 8 plugs and cyl 4 coil. Reset engine light. Been driving it a bit since then. Now in 4th gear ONLY the CEL flashes, shift to 5th and it goes away. I don’t know what the hell is going on. Weird. 2002 Mustang GT. 4.6 with SLP Long Tube Headers, Cats are...

Hey everyone! First post here! I just got my 96GT back from up north, sitting around for about 7-8 years and no upkeep... Long story short, pops just left it covered outside in the DC weather... I'm starting to work on it again and am having a ton of issues as you can imagine. For starters, i'm...

I have a 1998 Mustang GT had it in and out of the shop and they dont know what is wrong with it. It has a check engine light on for P0305 cylinder 5 misfire and that is all. The car has a slight miss when it gets warm in 3rd 4th and 5th when I try and stay a certain speed but only under light...