How much does it cost to install spark plugs in a 1998 Cadillac Deville
Fairly easy to do yourself. Check some youtube videos
I agree with Tom, you might consider tackling it yourself. I went to autorepair estimator and for the 4.6L V8 it's a low of $172 (using cheap Champion plugs, not the best quality For good iridium plugs bump that up $56, the Champion plugs are $3 and NGK or Ac/Delco iridium $10 ) and for plugs and wires both $330. Dealer price for same work $445 (plugs and new wires) Personally I think that is obscene, especially for your car.