Just finished replacing spark plugs and wires this morning on my 2001 Cavalier at 88,397K.

Ran it to the Supermarket (3 miles) for a loaf of bread and the engine felt smooth and remarkably renewed.

Upon my ride back home the car was slipping ("breaking Up") at low and high speeds (passing Gears).

Probable cause??

 

So at low and high rpm the car was missing? It could be the distributor, have you changed the fuel filter lately?

 

did you use too much dielectric grease?