Where you having these problems before opening up the engine for the timing chain replacement?
And when you say after 5+ miles that mean every time you drive it you can only go 5+ miles before It acts up?
It can.
On my 03 use the water hose to rinse off my engine. Unknowing to me water got into the spark plug wire walls. As soon as I started it up it sounded like crap and ran like crap. It was popping knocking stalling and sputtering. I was freaking out. But then I read somewhere that suggested...
Try a can of mass airflow sensor cleaner. I'm willing to bet. You probably over oiled your K&N. And got some on the MAFS, I've had the Same issue on my old 2v.
Oh re clean the air filter. And use little oil on it.
3 years ago hear in dallas tx, we had damn neer 2FT of snow and a 1" thick sheet of ice. don't get snow ever year but, we always get ice. and i've always drove on it with a lowered stick shift mustang. with cheap summer tires,