My 94 explorer runs good until I drive on the freeway about 100 miles or so.
After about two hours of driving it looses power and the check engine light
turns on . It still drives never dies but bad. If I pull over and turn it off for 15
minutes it will run fine for a short time 5 to 10 minutes then looses power
again. It shows codes for rich and lean fuel mix on both banks. Maf voltage is
ok chanced pcv,air cleaner . In town on 30 mi trips it runs fine. Help