4.6l slight rough idle
Hello everyone, new to the forum and I have found tons of great information! Bought a 2003 F150 Supercab XLT back in 2010 and after a couple of weeks I noticed a slight rough idle after the truck would warm up.
Well a couple months later it threw a check engine light and one of the cylinders had a misfire. Well all the plugs and coil packs were changed and it still had that rough idle. I then had a fuel system treatment done (was skeptical of the treatment even doing anything) and I noticed a slight improvement.
I have checked the PCV valve, checked for vacuum leaks and cleaned the MAF sensor. My mechanic who I have known for years and is very reputable in the community says he thinks it idles fine.
I found a ford service bulletin (01-24-8) that talks about feeling a shaking in the cab on certain trucks that have the seat belts integrated into the seats and they say its normal.
I have searched the forum and found some similar issues but not quite the same. Is there anybody with the same problem? Anything else I can check?
It is just a slight shake (more pronounced when in drive) but it bugs me like crazy. I take pride in my vehicles and want them to operate as they should. Sorry for the long post but I am looking for answers or to see if anybody else is in the same boat. Thanks!!
Last edited by Msufan; 01-17-2012 at 06:01 PM.