Buick Lacrosse 2004–2006 — technical service bulletin
Bulletin 3679 · NHTSA communication 10019236 · issued Feb 22, 2006
Technical service bulletin
communication type
Engine and Engine Cooling
component
2004–2006
model years
11
vehicle entries
Official summary
Service vme - diagnostic trouble code p0420 or p0430. *ak
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.