No fitting on Rail? Hmmm...Some one more familiar /manual with this car should chime in.
I have read this whole thread and I am hoping it gets better Dave. Lots of good info and parts are now installed.
I know on my 97 park ave I had rpm problems including a stumble and once I had cleaned the (IAC) Intake air control and ports and then started the car and continued to spray throttle body cleaner in at 1900 rpm things got better in a hurry. I shut car off and then cleaned both side of throttle plate and used q-tip on plate edges while holding throttle open, to remove as much carbon as possible, and to ensure a bit smoother operation.
Have you done a good tune up on this car ?-Fuel Filter, Air Filter, plugs & gap check etc? Hoping some of this may help & be applicable.
Luckily I have a friend with a smoke machine for finding hose leaks. I had a lean situation that was easily located to fix a cracked EVAC & other hoses on my wheels in quick order while on the lift. Now my PA purrs like a kitten with normal idle, smooth shifts. I did use platinum spark plugs too, which it really likes. In the spring I intend on removing the entire throttle body for cleaning as carbon sure builds up quick and I think regular service on throttle body should be done every 2 years anyways.
Best-o-luck I hope the stall problem gets solved....IAC clean effects the idle...
1997 Buick Pk Ave (Soft Ride) Suspension!