OK guys, I have an 06 Titan 4wd with 180,000 miles that is 100% stock. I changed the spark plugs about 3 weeks ago and after driving for about 200 miles the SES light came on. I pulled the codes and got only the P0430. So I reset the light and decided to put some mid grade 89 octane in her. She has been running great and my mileage is a little better since I changed my plugs. They are Denso Irdium btw.
So I drive for another week and put another 700 miles or so switching back to the 87 octane. Now the light comes back on last Tuesday. It ran that way for a week and now I pull P0420 and P0430 codes. So today I put some premium (93) in her and the SES goes off again. Anybody have a clue why this is happening? What would you do? Thanks for your thoughts!
So I drive for another week and put another 700 miles or so switching back to the 87 octane. Now the light comes back on last Tuesday. It ran that way for a week and now I pull P0420 and P0430 codes. So today I put some premium (93) in her and the SES goes off again. Anybody have a clue why this is happening? What would you do? Thanks for your thoughts!