you can replace the plug wires without removing the intake, you need small hands and have to lay across the COLD engine. If you run a search there should be post of how to do it with a bent screw driver (the post is 6 months or so old). 4.0 & 4.6 wires should interchange.

 

Mike,

You are right about checking the parts. The previouse service shop did not change two of the wires and charged me for the plenum removal.

I have had coolant disappearing. One day it just started leaking I tried to find the source but could not locate it. It just seemed to stop.

I had to leave town as soon as the repair was completed. I will look at the wires today to find out the brand.

 

Checked the wires and they are STI. The plugs I believe are Bosch.