1. Identify your engine: Look for an engine code (e.g., Northstar 4.6L, 4.9L, etc.) This is usually found on a sticker under the hood or in your owner's manual.
2. Consult a repair manual: Once you know your engine, get a repair manual specific to your 1999 Cadillac model and engine. These manuals have diagrams showing the location of all sensors. You can find these online (e.g., Haynes, Chilton) or at auto parts stores.
3. Use online resources: Search online for "[Your Cadillac Model] 1999 [Your Engine Code] crankshaft position sensor location." You might find pictures or videos showing the sensor's location. However, always verify this information with a reliable repair manual.
General Location Hints (but not guaranteed for all 1999 Cadillac engines):
The CKP sensor is usually found on the engine block, near the crankshaft pulley, often on the passenger side (right side when sitting in the driver's seat). It's typically a small sensor with a single wire or connector. But again, this is a general guideline and may not apply to your specific vehicle.
Caution: Working on your vehicle's engine can be dangerous. If you're not comfortable doing this yourself, take your car to a qualified mechanic.
