Car Running like hell

My name is Chris, I live in Bridgeport, CT. I have a 1997 Pontiac Bonneville SE. Well at 86,000 + miles I had the intake, starter and plugs replaced. Well This is my work vehicle I put 300+ | miles on MY car a day. Well RIght now the Engine or Transmishion is royaly messing up. The engine will not rev OVER 4000 RPM. When you go up hill and Cruise Control is set no sooner it needs more speed the engine or tranny makes a Hell of a noise and thats not all. When I am driving at a dead stop, and hitthe gas the car will move, and when I get up to 30-32 MPH the Engine/Tranny makes the noise. The car now has 106,000+ miles on it. The troubles only recently started. I cannot keep driving like this. I pulled the plug's and they look decent for 20,000 miles but the Check engine light comes on saying I have multipul misfires. I've sprayed stupp around the intake/fuel injectors to check for leaks, NOTHING. I tested the Ignition Coil Packs with the pen light and nothing they all seem to be firing correctly. The wires/plugs are damn near new. The wires are BOTCH from AutoZone and the Plugs are BOTSH Super gapped to .060. I'm thinking it might be the fuel filter because thats still orgional. But I run Fuel Injector Cleaner the fuel Injector cleaner thought it monthly. The injectors have been tested by a ASE Certified Machanic and tested fine. The wires are carring the current perfect. BUt I have run out of options as to what to test. I am on the road from 9am-7pm. I've had the transmishion worked on 3 times. Had it overhauled, Rebuilt, Drive piston changed ALL IN ONE YEAR. I cannot afford the $1600 to have that worked on again. I checked the CAT at night to see if it turned red as if it was running hot which would indicate ignishion probs. The drive belt is fairly new. Only had 15,000 on that. If anyone has any ideas please give them. I'm runing out of ideas, I'm thinking changing the fuel filter and plugs (upgrading them to Botsh Platnum 4). Please feel free to IM me or call my cell after 10am @ 203-923-7456 any help is greatly apreshiated. :banghead:

There are several areas I would check and the first thing I would look at is the cat. It sounds like it is going bad, even though it is not showing any external signs it could be blocking and causing you to lose power. The second item I would check is the fuel pressure. When you demand fuel you are not getting it. This could be a fuel filter blockage that is causing it so changing the fuel filter will not hurt. Once the filter is changed have the fuel pressure checked. It should be between 40 and 45 pounds when you hit the throttle to accelerate. Anything less could indicate that the fuel pump is going bad. I thing the multiple misfires could be from a lack of fuel. If everything checks out, check the mass airflow sensor and clean it, also if nothing else helps check the crank position sensors to see if they are going bad. Hope this gives you some ideas on where to look.

I don't know if you have solved this problem, but I had a problem where my 95 Bonneville wouldn't go over 4000 rpm's and lost speed uphill, despite that it normally gains speed uphill easily. It also ran fine until I hit 25-30 mph and then it started making a lot of noise from what sounded like the tranny. I took it in to my mechanic and he suggested replacing the nose clip on the super charger and the rings...those are known to go bad on Bonnevilles apparently...no problems whatsoever since then. He showed me the rings upon removal, and they were all broken..every last one. They were stock...I forget what he said they were made of, but it was some material that didn't flex like rings need to. He replaced them with much better after stock rings. I hope this helps you somehow. Good luck.

GMLoyal