I own a 2009 E350 CDi coupe with under 72,000 miles, which I acquired at a low price from a friend a few years ago. It is mostly used for short trips to the gym or grocery shopping, since I work from home. Not optimal for a diesel, I acknowledge.
My engine light has begun to pop up with fault code 148a00, which my code reader states is "The number of times the regeneration of the diesel particulate filter was performed is too high".
The 1st time I reset it, placed 2 bottles of Wynns DPF cleaning in the tank and then drove it down the freeway for 90 minutes. It was satisfactory for a month, but then it returned. I undertook a similar endeavour; however, the drive lasted just an hour, and now, a week later, the light has reactivated.
Is this the DPF itself, or a sensor, and what are my options?