QuestionCar was running fine put some driffent gas in tank. Car misfires an sputters. It run fine an then start spitting like not enough gas are something. Then misfires. Done use new tank of gas an cleaners. No codes that i can see,no engine light on.
AnswerKeep runnin 93 octane, over time youll clean the injectors and motor out, you cant mistreat the old caddy motors, i learned this the same way, cant even put 91 in my caddi and i have a MSD blaster hei coil.
What you might have to do is replace the spark plugs now, but before you do that clean out your throttle body of carbon deposits and where your pcv valves are with air intake cleaner, and then change the spark plugs, filler up with 15-40 diesel grade oil, or mobil 10-30 and enjoy.
