2001 Blazer Automatic started jerking

[quote:a2ee616811="rockychevy"]2001 Chevy Blazer; 57,000 miles; Automatic; 4X4

While driving on the highway several days ago, my blazer started "jerking" ever so often when I reached higher speeds, around 65 mph. Been doing it ever since. Will drive ok for a while, then the jerks start. Tend to notice more in the afternoon. Thanks for any help.[/quote:a2ee616811]check the inside of the distributor cap for corrosion.also check for poor connections at the cap where the plug wires go into it.If this doesnt show anything, you can remove the crank sensor located in the lower part of the timing chain cover and check the sensor for any marks where it might be contacting the reluctor ring.