Well my 03 ecursion (late 03 build, hope it has the good threads!) just got the 05 frontend conversion and should be coming home in a few days. I was thinking with 73K miles its time for new plugs, boots?, pre-cat oxygen sensors, air filter, and a PCV, and possible EGR valve? I like to do things thee right way the first time so I figured I'd cover all the parts that tend to start acting funny as the mileage adds up (egr valve). Am i fogetting anything? Should I look for or avoid certain brands? I know I dont want bosch oxygen sensors (they just arent a quality part in my opinion) so I am thinking motorcraft for these. I cant seem to get my mileage over low 11's so I am starting to suspect the oxygen sensors are starting to get slow. I am hoping to gain a lil mileage by getting some fresh parts in there.

Any advice on cleaning the holes out before I pull the plugs out? Dont want junk getting into teh combustion chambers. Also, any of these plusg a pain to get to? As in having to move other stuff to get access to them? What about EGR and PCV placement. Where are they? This is a new motor to me and I am not familiar with the ford modular motors other then doing plugs on my buddies 99 clown victoria.

 

After pulling wires, blow out around each plug real good, spray some jump out juice (penetrating oil) in the hole and let sit for 10 minutes, you don't need alot, just a good shot for good measure since the 10's are known to have tread problems. When reinstalling new plugs dab a little never sneeze (thread lube) that annoying silver stuff, that will insure lubing threads and staying lubed.

 

You maybe surprised what a clean fuel filter can to for a V10 - may not get better MPGs, but it will use it'll use it better.

 

I'd say you've got the bases covered for a mpg tune up, though add MAF cleaning (in case you didn't know, sits just downwind of the airfilter, remove it and spray the heck out of it with MAF or electrical cleaner, both available at your favorite parts store) into the mix and then reset the computer (pull battery cables and let sit for 15 minutes with headlights turned on to drain all capacitors in the system)

Also, after you crack the threads on the plugs and back out a turn or two, blow the hole out again. Removing the entire air intake back to the throttlebody will make lift much easier. Don't mess witht he injector rails. Removing the PCV hose to the throttlebody helps as well. Remove everything that you can easily remove that looks to be in the way at all. The job took me less than 3 hours and that was helping watch a 12 month old child at the same time.

You may want to look at replacing the shocks and steering stabalizer plus the sway bar links are quite possibly shot by now as well.

Make sure you get O2 Sensors with long enough cables, there are a number of lenths and I don't remember what I used.

Good luck

 

I was eyeballing that steering stabilizer lately actually so I will have to see what a new quality one goes for. Shocks seem to be doing well still even after driving around the pothole filled chicago streets for the last year or so. Good thing you reminded me about cleaning the MAF, slipped my mind.

has anyone narrowed down when in the 03 build year the new heads starte dto be phased in? Maybe make a poll asking the 03 guys what month they were built and if they had the good or questionable threads?

 

If your shocks are original you really do want to replace them. I thought mine were all right but couldn't believe the difference after I put the new ones on. Bilsteins are great shocks, though they don't make a steering stabilizer.