Recently I change out my ignition wires with Omi Sparks and plugs with Autolite XP 103 (gap set at .054) plus my air filter and now my vehicle has an intermitted hesitation at idle, but does not stall out. I then change out my fuel filter with Motor Craft replacement and still no improvements. The vehicle was running find before I change anything out, but my gas mileage had decrease. It has improved with the tune up, but now the hesitation has started. Other than regular maintenance with oil/filter and air breather change out the only changes I had done was my spark plugs at around 80K miles with Bosch platinum. Currently my vehicle has 104,000 miles.

Any suggestion on why it hesitates now on idle intermitted? Should I put the manufactures MotorCraft ignition wiresand plugs back in?

 

This is a follow-up on my last post. I found that one of the plugs had a crack in the ceramic.Changing the plugs is a pain, but if you remove the front tires you can reach all the plugs from the tire fender wall. When I put in the new plug, it must of cause a crack in the plug not using the proper spark plug socket to tighten it down. Once I isolated this problem and replaced the plug the problem was solve.