1991 Oldsmobile Cutlass Calais mileage: 95,000. After driving the car for a few miles, it bogs down, sputters and then dies. After letting it set for a few minutes it starts up, but in a few minutes it starts over again. I have replaced the computer and I had it hooked up to a computer at the service station and checked spark plugs. It is very hard when you come to a stop light and it just gets worse as you drive. Thank you for your help.
Check the catalytic converter to make sure it is not plugged or restricted. To test for a plugged converter, drill a small hole in the exhaust pipe right before the catalytic converter. Install a temporary hose fitting and attach a long rubber hose and a 0 to 10 pound pressure gauge. With the gauge inside the car, drive up a hill or accelerate and read the pressure. Normal is two to three pounds, restricted four pounds or higher. The drawback to this method is the small hole will need to be welded shut after the test; a minor job if you have a welder.