Where is ignition coil 4 in Lincoln ls?

The Lincoln LS ignition coils are not numbered 1 through 4 in a way that's easily visually identified on the engine. They're arranged differently than some other vehicles. Instead of a single coil per cylinder, the Lincoln LS uses a coil-on-plug (COP) system. Each spark plug has its own ignition coil mounted directly on top of it.

To locate ignition coil 4, you'll need to refer to a repair manual specific to your Lincoln LS's year and engine (there are a few different engines that were offered). The manual will have a diagram showing the cylinder numbering and the corresponding coil location. The firing order is crucial to correctly identify cylinder #4 and its associated coil.

Without knowing the year and engine, I can't give you a precise visual location. However, generally, all the coils will be near the top of the engine, directly above their respective spark plugs.