I posted last year about some miss problems. Got that one resolved then it developed another miss. 99 v10 with 140k on it. It's been trouble free except for the miss late last year.

The miss is weird, comes and goes. Sometimes for a day, some time for 5 minutes. Sometimes I could rev it and it would go away. I thought my problem was a tranny lock up problem. My daughters 98 Mustang will whutter at about 45-50mph...at the verge of OD shift. Happen to be listening to a car guy and he said that was the clutches shattering and you can add some tranny additives to cure it. BTW I added some Lucus oil to hers and it seems a little better. Any figured that was not my problem but at the same speed mine would shutter like crazy.

Finally took the time yesterday to do the pull the coil wire trick again to find the miss. Found it. Little oil had gotten around the plug but the sealed plug looked to be dry inside. Fiddled with it a little bit and removed the screw in prep for a auto part store parking lot switch out. Low and behold the miss is gone! Driving around yesterday, fine, this morning, fine. I remember in my last research that someone determined that the plug itself can be a problem. So I'm holding off on replacing the coil at the moment. But I plane on cleaning the engine bay, it could use it anyway. One smooth engine when it is hitting all 10!

Rob