Hi Guys,

I have an 02 S55 AMG. The car has 176K on it and running fine...... Lately I have had the check engine light. My Mechanic scanned the car with Star Diagnostics a few weeks ago. The exhaust congestion code is coming up. I had many mechanics suggest many things including replacing the aft O2 sensors first instead of replacing the actual cats. $$$$$$$

I had one of the rear cat welded after beginning crack due to weak motor mounts last year.Wondering if the rear cat may have been damaged and causing the restriction. The problem started soon after this repair was completed???

I need to register the car in California now butI know I wont pass the smog test with this condition?

Any comments/suggests welcomed!!!!!!!

 

The exhaust congestion code is coming up??

What code ref is that? i.e. P0XXX?

Cat inefficient is a pssibility but would hazard a guess its the rear O2 sensor on the side that is giving the problem.

To save money swap sensors from left to right and see if problem moves across the car. However maybe your time is more valuable than the cost of new sensors. Ensure you use genuine MB / Bosch sensors

Good luck,

Stuart