1990 LeSabre hesitating-need help diagnosing

I have a 1990 LeSabre that runs like a champ until it gets warm...... Then it sounds and feels like a spark plug wire has come off. (Chugging and hesitating) It runs very rough until I turn it off and it gets cold again. If I accelerate while it is running rough it will still get up and go, all the while still running rough. It has not lost any power at any time. :banghead: The vehicle sat for a while with a full tank of gas and I was told that the gas may be bad and to add treatments for a few tanks. That has been done. Still not working.

I have had different people tell me different things (catalytic converter, sensors, fuel pump or fuel filter). I appreciate any advice anyone can give me. Thank you

I have a 1990 LeSabre that runs like a champ until it gets warm...... Then it sounds and feels like a spark plug wire has come off. (Chugging and hesitating) It runs very rough until I turn it off and it gets cold again. If I accelerate while it is running rough it will still get up and go, all the while still running rough. It has not lost any power at any time. :banghead: The vehicle sat for a while with a full tank of gas and I was told that the gas may be bad and to add treatments for a few tanks. That has been done. Still not working.

I have had different people tell me different things (catalytic converter, sensors, fuel pump or fuel filter). I appreciate any advice anyone can give me. Thank you


Some ideas: Spark plugs, plug wires, carbon build up in intake, injectors, fuel pump, fuel filter, air filter, oxygen sensor, MAF sensor, ignition module/coil pack would be my first guesses as things to check. There is no one magic answer without someone testing your vehicle. You will have to check each thing or replace parts. It is cheaper to pay someone to diagnose than to replace several parts if you can't fix it yourself.