Why is my van sputtering after 45mph.
I was on the highway doing 70 mph. I then being to accelerate to 80 mph.
My van began to appeared to be misfiring. I then slowed to 70 yet it still
happened. When I exited the highway and was driving 55 mph and under the
sputtering stopped. The following day it continued but I noticed it would only
do this after engaging in 4th gear. This year I have replaced the spark plugs,
wires, coil pack and fuel filter. My only other assumption is my 4th gear is
slipping or fuel pump.