small problem

i have an 01 explorer sport with v6 sohc. i have noticed a slight shaking or bucking when driving at a constant speed say around 40mph to almost 60mph. the check engine light was on before and it was an egr code, i replaced the egr and had the check engine light reset. it hasn't popped back up. but the shaking or bucking is still there. it does idle alittle rough, but not as bad as before the egr was replaced. i noticed that it doesn't do it when the cruise control is on. it almost sounds like a missfire to me but i am not to sure.

You description does sound like a misfire. If you have access to a scan tool with the Component Parameters setting, you can monitor the individual cylinder misfires, even if they are not high enough to cause a check engine light.

-Rod

thanks

well i have a way to check if the cylinder was missfiring but i did replace the dpfe sensor, because of a po401 code and it did fix the problem