5000 miles on everything. idle is up and down, alittle miss at idle, runs great then 15 minutes feels like someone is holding on to the back bumper and wont move no matter how hard on the throttle, gets 9.1 mpg, hessitates at take off, new motor, plugs, wires, cap and rotor, new tps, no vacuum leaks just did the propane test, 244,000 on car before rebuild 5000 miles ago, dont know if the o2 sensors have been changed ? and dont know if the fuel injectors have ever been done ? just passed smog 3 months ago. help i'm ready to donate it to a charity, i love the car but cant stand how its running. thanks for any suggestions...