Dealer service item.
spark plug replacement on a 93 Cadillac DeVille 4.9 liter
Northstar engines have freeze plugs in the heads! Two are in the right head and one in the left. They can be found on the exhaust side of the head and therefore difficult to see.
A 97 Deville would be equipped with the Northstar V8 engine, therefore, it has 8 spark plugs.
Spark plugs are easy to change. One disconnects the batter and spark plug cables, and removes the old spark plugs. Next a person puts in the new spark plugs, then reconnects spark plug cables and the battery.
double platinum Bosch gapped at .55 - pretty standard stuff!
where are the sparkplugs on a 2002 cadillac deville and how to change them
How can I change the wiring and spark plugs on my 1996 Cadillac Sedan Deville Concours?
Recommended change is 100,000 miles
at the end of the heads
Pull wire off the spark plug