My mother has been complaning that her car (1996 Intrepid 3.3) just doesn't have as much go as it used to. Soooo...dad and I replaced the plugs and wires as an easy starting point. Crank it up, it runs like hell. OOOPS...forgot to reconnect the TPS, O2 sensor, MAP & air intake temp sensor that I unplugged to get to the #5 plug & route the plug wires. Plugged all that in, now it runs. But it idles slightly rough, backfires if you open the throttle too fast, and there is an occasional miss. I think OK...maybe the computer is pissed off because we ran it with half the engine bay disconnected, so I disconnect the battery, step on the brake, and leave it disconnected for a few minutes. Start it back up, same thing. Maybe a new part is bad, so we start swapping out old with new to isolate the problem. No love. Put all the old stuff back on there. Still runs crappy. I checked the computer for codes, and only got 12, which is "Battery has been disconnected within last 50 key-on cycles". Dug around the engine bay for vaccum leaks or anything of the sort, couldn't find anything. Without being able to see what's going on inside the computer, I'm at a loss as to what to try next.