I think Ford's claim of 100k mile tuneups is a little on the optimistic side. I changed my plugs this evening (99.5k miles) and the electrodes were down down to almost nothing. I'd say 70k tuneup intervals are a little more realistic. I put new Autolite Platinums in, and it made quite a difference. I thought the idle was smooth before.. Now, you have to really pay attention to notice that the engine is running! I was also impressed with how easy the plugs are to change on the Duratec.. I was anticipating quite a battle for the rear bank, but it was cake.
The rear O2 sensor, on the other hand... I'm not gonna talk about that.
At least it's replaced now.
