Quote:
Originally Posted by catmandoo62
freeze frame tells you what was happening when it threw the code.i carry my scanner in my suburban because if say i'm cruising along and have to hit the brakes all the sudden it will throw a pp420 code which is a bad catalyst.but that is not my problem.i can drive this thing for 5000 miles and if i don't have to get on the brakes hard it does not throw a code.i bought mine at o'reilly's for like 120 bucks.well worth it.
|
P0420 is a general code that might be caused be a number of faults. Most of the time it IS the cat gone bad, but it could be something else. This is the situation MS Fowler is complaining about. A more advanced code reader such as a Scangauge can be used to compare the front and rear O2 sensor's output and help identify the fault.