Well unless the vipers are screwy which I don't think they would be, the codes for the engine will probably show as PXXXX, x's as numbers though, p is for powertrain.
http://www.dsctunerhaven.org/forum/viewtopic.php?t=1414 heres a link about some obdII stuff posted in general a few days ago if this helps you.
I'll google around for ya and try to find some DTC's(Data Trouble Code) for ya though.