2000 Nissan Maxima engine lights on cylinder 5. what is a 5 means?

A "cylinder 5 misfire" (or similar code related to cylinder 5) on a 2000 Nissan Maxima's engine light means that the engine's ignition system or fuel delivery system isn't working correctly for cylinder number 5. The V6 engine in that Maxima has six cylinders arranged in a V-shape; each cylinder is numbered sequentially. A problem in cylinder 5 prevents that cylinder from firing properly, leading to reduced engine performance, rough running, and potentially damage if left unaddressed.

The "what does a 5 mean" is simply indicating that the problem is isolated to that specific cylinder within the engine. The cause could be various things, including:

* Spark plug: A faulty, worn, or fouled spark plug in cylinder 5.

* Ignition coil: A problem with the ignition coil responsible for delivering the spark to cylinder 5. (These cars often have individual coils for each cylinder)

* Injector: A clogged or malfunctioning fuel injector preventing proper fuel delivery to cylinder 5.

* Valve problems: A burned, bent, or stuck valve in cylinder 5. This is less likely but possible.

* Compression issues: Low compression in cylinder 5. This could point to a more serious internal engine problem like a worn piston ring or a damaged piston.

You'll need to have a mechanic diagnose the precise cause of the misfire in cylinder 5. They'll likely use a code reader to get more specific trouble codes and then perform further testing (like a compression test) to pinpoint the problem.