1997 Deville Knock Sensor

[jdueitt]

I have a 97 Cadillac Sedan DeVille with 4.6l. Recently, when I accelerate hard, I get a detonation knock in the engine. Does this sound like the knock sensor going bad. Where is this sensor located on the engine??

Thanks

[M.A.C]

I believe you will find the knock sensor for your Northstar under the intake manifold. The 93 through 95 Northstars’ had the knock sensor on the outside of the block on the right hand side of the engine beside the trans.

Also, the knock you hear could be caused by carbon wrap or carbon build-up. It could also be caused by a lean fuel mixture caused by a defective fuel pressure regulator. Does the car start OK when hot? If you are increasingly finding it more difficult to start when hot or when it sits after you have driven it, this indicates that the fuel pressure regulator is defective. If it backfires through the intake manifold when starting then it is a sure sign of a defective regulator. What about the spark plugs?

Northstar engines should be driven briskly from time-to-time to clear out carbon build-up. As you are probably aware, Northstars' burn oil. This can lead to carbon. Do a Wide-Open-Throttle (WOT) by shifting to second and at about 50 punch it up to about 60 or 70; let off the gas and allow it to coast down without stepping on the brake. Do this a few times. See if it helps.