1995 Riviera Keeps stalling

I'm have trouble with my 1995 Buick Riviera. I brought the car last summer. I had a upper intake failure witch i heard is common for 3800 series 2, i fixed that along with a new water pump. After that it seem like everything was running fine until it started to get cold outside then when i go to start it would start right up than immediately die, Some times it would take 7 if not more try's before i could get it running. but the worst part it will also die randomly while driving. It does start right back up. I think it happens while accelerating. When it dies while im driving the battery light starts to flash at the same time the rpm start to flicking and if im on the gas the rpm will go up to like 5000 than it dies to 0. With the music still playing and the light on and my new battery i doubt its a battery problem. i did change the coil pack with ones from the junkyard witch temporary fixed the problem for only a couple days. Also my car only starts in park i wanted to know if there a way i can bypass my neutral safety switch, so that when my car dies i can put it in neutral and start it instead of having to come to a complete stop and restarting it in Park. I don't know what else to do. So if anybody has an Answer please help me? Thank you

Any bets on how long before this thread gets moved? (btw lorleakriv, this is the wrong forum area to post this)...

See this thread regarding Series I dying on the highway: https://rivperformance.editboard.com/t9473-car-dies-abruptly-on-the-highway?highlight=dies

To sum that thread up: Generally, a fuel problem cuts the engine off slowly with shuddering. Electrical probs will generally cut the engine out suddenly and abruptly. Issue could be ignition switch or crank sensor perhaps? Maybe plug wires?

As far as starting in a setting other than “Park,” this may or may not help… really not sure: https://rivperformance.editboard.com/t5428-delete-brake-to-shift-express-down-24hour-power-port?highlight=delete

I don't think anyone here can give you a definitive answer to your problem by your symptoms, but maybe we can narrow it down for you. I have a few questions that may help someone come up with some suggestions.
-is your check engine light on?
-when you say the rpm goes up to 5000 then it dies to 0, is the tach just jumping up to 5000, or does the engine rev to 5000rpm and then the car stalls and tach reads 0?
-I assume your battery is new, but what is the condition of your connections at the battery and at the terminal under the hood? Also are the grounds all clean and secure?

Anything else you can think of and state clearly would help.

Ignition Switches LOVE to make the car die randomly and cause electrical "glitches". It is also VERY hard to diagnose. It's usually a last effort try at repairing a ghost (because by then you've replaced everything else   ).

When my Ignition Switch failed, the car would just randomly die. Sometimes it started right back up, sometimes it didn't. I even drove around with a test light hooked up to the Ignition feed to the Ignition Module, stretched out taped to my window. The car didn't die for the next 2 days....I was looking for a loss in Ignition power when it would die. Eventually it happened. The car died in traffic,  and the light went out. THAT'S when I replaced the Ignition Switch. Mind you, this was after the "usual" suspects were repaired with fingers crossed.

The electrical glitches you're having at the same time could absolutely be caused by a failing Ignition Switch, being that it supplies power to basically everything in the car when it's keyed "ON".

I'm just laying some info down about it, because my mind went right to Ignition Switch at first read. I suggest you find a trusted mechanic and see if they can't diagnose it for you. It could definitely be something as simple as loose battery cable, or a corroded ground. Our cars electrical system shares many + and - connections. If one gets nasty, it can/will do bad things in many different places....