Pontiac Repair: 2000 Bonneville SE with 3.8L Runs Rough, fuel pressure regulator, pontiac dealer

Question
Hello,

My wives Bonneville suddenly started running rough while she was driving it.  I have driven it and it runs like it is starving for fuel and stumbling terribly when you accelerate but there is no service engine light.  It idles okay but is barely driveable if you accelerate very slowly, although it will still hiccup and buck a little.  If you get on the accelerator it really stumbles.

The car has 96K miles on and within the last 10,000 miles I have replaced the fuel pressure regulator, mass airflow, plugs, plug wires and fuel filter.  She put in gas from a station that doesn't move a lot of fuel but has driven a 1/4 tank before this problem showed up, which she said was sudden.  I put a can of Seafoam in and drove it around but still the same.  ANY HELP would be greatly appreciated.

Thank you in advance for your response.

Roger  

Answer
Hi
Really sounds like a restricted Catalytic converter to me.
You can take it to an exhaust shop and have them diagnosis it further, but I have seen A BUNCH with the same symptons.
Check also with your local Pontiac Dealer and make ure there is not a special extended policy from GM for that particular converter. I am not sure. If not a Universal Converter will work just as good.
Just advice from Experience.
Hope it helps
Good Luck
Paul