Why is oil coming out the top of my engine?

Cap wasn’t misaligned? Is the gasket on the cap still in place?

 

How much oil did you put in?

 

Did you check the oil level right after the change too, and after running a few minutes? It can be tough to read, especially when very clean. I'd suggest to pull and wipe the dipstick, then wait a good five minutes before pushing it back down for the check. This gives the oil in the tube time to run back down, you get a clearer reading.

How many miles on the car btw.

 

This check was immediately after the oil change? Did you run the engine before doing the level check? If it not, and assuming the oil filter was changed: until the engine is run the oil level will read at least a cup high, since oil hasn't flowed back into the oil filter zone.

A lot of assumptions and grasping at straws in the above.

 

I think (and I could be having a senior moment right now) that the car gives a check engine light if the oil cap (aka the 710 cap) isn't secured because it messes with the internal pressures in the engine. But I can't think of another reason that oil would have escaped.

 

Pcv valve stuck.
Pressure build up in the oil
Guess what next

 

Here's what I'm thinking:

1. You under-filled somehow, and checked the oil right after the change, without start up, so it was higher than usual. Once the engine had run, the oil filter filled, it dropped. You also spilled a little oil while filling.

2. Noticing the oil was lowish a few weeks later, and seeing some oil spill, you connected the wrong dots??

Could be way off the mark, but it's a relatively benign, no harm done scenario. Wipe off the spill, top up the oil, continue to monitor level?