Re: Sputtering and Misfire issues in Drive and Reverse
Time to drag out the timing light and verify engine timing - you may have a jumped timing chain (not likely!)
Also, triple check ALL wiring. One suggesting is to take a dark night, start the car, and fog the plug wiring with a mist of water.
In my personal experience, #1 and #3 spark plug wires are right royal pains in that it's easy to feel like they're on, but they'll jump right off. I had #4 cylinder give me fits my first tune up until I finally got it seated properly.
Also, there's a chance a coil pack has failed or is failing. This would tell you (the misting with water) due to the corona and sparking you'd see.
It's also time to check the fuel line pressure with a fuel line pressure gauge (they're cheap at Harbor Freight, albeit not very accurate.)
335K miles on original motor and tranny (only motor work 2 x LIM replacement), Monroe SensaTrac struts front and back (new at approx. 300K miles), and Alero discs in back. LS fogs added with custom wiring. HID high beams, HIR low and halogen fogs. Raybestos Pro Grade front rotors and Bendix D747 ceramic pads on front.
Addendum: Rest in peace. Surge tank blew, motor overheated, I think she's lived a long and useful life.