- 1998–2004 Factory-verified
the 1998 list requires WX4; the 2001–2004 lists name rear YPA and the 2001–2002 lists require B4U and P42
XPA Factory-verified
Also documented for ChevroletPontiac
Documented applications
This page aggregates every documented appearance of XPA in the Oldsmobile reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.