OK, the warm weather finally arrived and I did the job. It did take every bit of the 3 hours that people talk about. What an incredible amount of work to replace one stupid sensor! I spent most of that 3 hours designing punishments for the engineers who allowed it to end up back there...
Here are some comments on what I found and did.
I got the Snap-On socket made for the task and so should you. Dead simple with that thing!
I flipped a coin and decided the "in from the top" method sounded simpler than the "up from the bottom" method. But you know what? I did both, and I am not sure how you avoid that. I went in from the top and that allowed me to pull up the wiring harness to work on it to splice in the new connector. I don't know how you could do that purely working from the bottom...unless you didn't replace it, but that seems unwise. Mine was completely oil-logged. But what I couldn't do from the top was get the socket on the ICP sensor! That stupid heat shield is in the way, the one you remove when going in from the bottom. I guess you could avoid that if you didn't use the socket, but that would be insane, in my opinion.
So I worked from the bottom to remove the heat shield, which allowed me to get the socket on the sensor... and hey, from down there you don't need any crazy u-joints or anything. Just slap a 3/8" drive ratchet handle on the socket and it comes right out. You can easily turn it by hand once you get it started. Threading in the new one is... "interesting" since you're kind of working blind, but it's doable.
I didn't drop the front drive shaft. Working around it was not really any big deal. Much bigger deals were: The sharp protrusion at the bottom left rear edge of the block; the auto trans dipstick tube; having to take out that (*&*&$^&&**(())_(_)(#
[email protected] air filter when getting at stuff from the top.
Getting the heat shield back on was "fun" but doable. As long as you have skinny arms and can thread bolts into holes with one hand while not able to see what you're doing. Once you get it to stay in place with the first one in, it gets easier.
The from-the-top instructions mentioned removing a bolt on the back corner of the manifold. I was picturing an exhaust manifold bolt and my long nightmarish history with those snapping off on vehicles, etc. No, no, no, this is just a little stud that is there to bolt a ring terminal ground wire down to. Easy as can be to get out and put back and you *do* want to do that or else you will gouge the living crap out of your arm back there.
I managed to just unbolt the expansion tank and remove the little line that leads over to the passenger side, and just lay it over on its side while still all connected... this avoids the huge mes of draining it and removing it completely. You lose a few ounces of coolant, that's all. (OF COURSE make sure to relieve pressure before removing that little hose! Then put the cap back on tightly.)
Same deal with the FICM - I undid the 4 bolts holding it down (plus the bracket that covers two of its bolts and connects to the intake tube) and then just leaned it over to the left side of the compartment. I didn't hassle with removing all the connectors to it.
The air filter and upper intake tube were removed to make room for all those laying-over pieces, and for me to lay over the engine - I put a folder-over moving blanket across everything and just surfed back to where I needed to work.
Have a good bright small flashlight that you don't mind getting greasy. It helps a lot when trying to spot stuff back in the nether reaches (the ICP sensor, the bolts for the heat shield, etc.)
Cleared the code with a reader and it's been off ever since. Hasn't done one of its occasional surges either. By golly I think that's fixed!
Duncan
