So I have a 96 es 300 I have done the timing water pump starter radiator thermostat valve cover gasket pvc valve and much more but i got her running and drove it fine for like 3 days then it stalled and start smoking and misfiring so I found out the cat was clogged so I put a straight pipe in I understand but the greatest but ive put so much money and time in this car and I love it to death but I just can't figure this out ive checked 4 ground wires and cleaned them but still same problem my only thought is the ecu but I dont wanna change it unless I'm sure thats what it is please help any advice will help by the way I also did the fuel pump brand new oem