My ? is i have a 98 3.8 mustang and it feels like it is running on 5 cyl instead of 6.What i mean by that is when i am at a stop light with it in drive it shakes the whole car like it is skipping,but when i put in neutral it seems to run fine.When i take off from the light it spits and sputters and then it takes right off.Also going down road at about 45 to 55 it acts like it stills skips,i took it to the ford dealer (what a mistake) cause the engine light came and it pulled a code and the o2 sencer was bad cause it was runnig rich.The dam thing is still running like sh-t,i havent checked for vac leaks yet.Does anyone know what the prob might be? PLEASE HELP..

 

plugs and wires. change them see if it makes a difference. IAC valve might need a good cleaning. change the PCV valve while you at it. look at the contacts in the coil pack for the plug wires if yoiu have any carbon scoring then the pack should be replaced. how old is the fuel filter? check all vac lines to make sure you don't have a slight leak

 

Thanks cobra, well i done all that and things are fine but i never changed the fuel filter so i will change that and see what happens.Also i did find a o2 censer that wasnt working as well as it should it wasnt pullin the volts that it should,so i got a buddy changing it now so i will see if that is the prob.....