I am also bone stock, and have sort of suspected a cam timing thing for a while, but I have no way to really check that. My car is a 5MT though, so I generally know what gear I am in, and my RPM is solidly correlated with my wheel speed in any gear.
This sounds like the ECU reset and forgot any of its long term trims. Whenever mine resets (happens after a battery disconnect mostly) it idles funny for a few minutes. Maybe your ECU had been pulling timing due to the 87 the previous owner used, and now it's not?
I cleaned my MAF sensor this weekend and my stumble went away completely. We'll see how long it lasts, but it was dirty because the previous owner installed a K&N and I haven't changed back to a paper filter yet.
No, no compromise. I was just curious. I can't really think of any scenario where I wouldn't have said I could live with it, unless hitting the trunk button would cause the alarm or a violent explosion or something.
Sorry to dig up an old thread, but what happens with the wagon's rear hatch? I saw a link to another thread about adding the rear door, but after that what happens when you press the "trunk" button? I didn't want to ask over there because that thread has been dead for years (and somebody was being a total weinie about this mod)