Northstar Engines and System Technical Discussion Discussion, spark plugs in Cadillac Engine Technical Discussion; I have a 97 Deville with a Northstar. Someone told me I could change to a different spark plug (can't ...
Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
MD Eastern Shore - Kent Island
Re: spark plugs
Your car was supplied with the GM plug sourced from DENSO which is now known as ACDelco Professional Platinum #41-950. It's all you need, 87 or aviation 110/120 gasoline.
Whatever your owner's manual calls for is the fuel you should run for maximum efficiency, BUT the Northstar uses a knock sensor to detect fuel/mixture problems, so you can run 87 with a loss of a tad of performance.