Last night I went out and went nutso on the wiring in the engine compartment. I focused on the two areas I thought might be involved and could actually get at (o2 sensor isn't accessible on the ground), the Knock Sensor and the AMM.

First I pulled both connectors off and looked over the contacts. They all appeared fine, nice and shiny, with no signs of discoloration, oxidation, or damage. Then I went at the wiring. I cut back the sheathing further than I have in the past and gave it a look see. Everything seemed in order, but I cleaned up some previous patches and overall just straightened things out a bit. Then I carefully reconnected both terminals to the units.

Today I took it out and... full boost without a hitch. In fact, the wierd stumbling boost problem didn't resurface over a 15 mile drive that includes a 3 mile 8 degree incline (during which I boosted periodically).

So, I'm now assuming it's either a connector or wiring issue, and involves either the AMM or the KS. The former is the more likely given your experience and mine, but I touched the KS too and can't rule it out. However, faulty AMM connector or wiring would DEFINITELY fit with your replacing the AMM, having it work, and then having it die again. It would be likely your jostling and reconnection straightened things out temportarily, and it then just kind of settled into its old problem down the road.

Inspect the harness closely and the connectors, maybe clean it all up a little bit, reconnect it and see what happens. Cut back the sheathing on the harness to make sure it isn't falling apart inside the sheath. Post with a follow-up to let me know if this works for you too.

good luck,
rt