P0300 Jeep Liberty 2006

Question

Running rough under load computer catches it at around 3000, can feel it at 4000 rpms. Had dealer Service the throttle body and fuel injection system. Replaced spark plugs. Basic engine tune up.

Answer 1

Did the dealer tell you that servicing the throttle body and fuel injection system will fix the problem? if they sold you that and it did not fix it they are requested to fix the issue if they are charging you to fix a problem.

try to use 91 octane from Shell and see if that fixes the problem, or you may need an intake flush if there is carbon deposit on the valves.