fuel system

[saltyjim12345]

Often,but not always when I go up a steep hill,the van starts misfiring and continues misfiring for many miles.The fuel filter has been changed and I'm sure there is no water in the tank.

[carriedi]

it's possible that you don't have enough fuel pressure and going up a hill takes more fuel than the pump puts out and it takes a while for the pressure to catch up afterward. Or it could be that you have a problem with the secondary ignition jumping to ground somewhere other than the spark plug under a load. Once that happens it's easier to jump outside the spark plug circuit and it will continue until the spark plug becomes the easiest path to ground again.

a bad ground that moves when the engine is torqued under a long acceleration.

does your service engine light come on? Or is it on?