Driving home for the holidays, going about 60, my RX350 vibrated a bit and the check engine and VSC lights came on. From that point forward, I would experience vibration at 70mph or so. Ran it in 4th gear and things seemed to smooth out a bit.
Ran it over to AutoZone this morning to see what the codes read. Here is the list; in order
PO301- C1 misfire
PO300- random misfire
PO302- C2 misfire
PO303- C3 misfire
PO304- C4 misfire
PO305- C5 misfire
PO306- C6 misfire
PO354- Ignition coil D primary/secondary unit
PO301- C1 misfire
PO300- random misfire
PO302- C2 misfire
PO303- C3 misfire
PO304- C4 misfire
PO305- C5 misfire
PO306- C6 misfire

They suggest replacing ALL ignition coils and spark plugs. They are $100 a piece or $370 for all 6. What do you guys suggest? I cant imagine that all of them need to be replaced or that this could even be the issue.

 

Clear error codes first, Drive and see.

 

Def clear the codes and retest. Reading what you listed it looks like coil D which is cylinder 4, middle one on front facing bank.