I have a 2004 Ranger with a Duratec 2.3 liter 4 banger and stick shift. I took it to the Ford dealer a couple weeks ago for an oil & filter change; I got it back and drove it for a couple weeks, but I kept smelling some sort of fumes as I drove it... like I was catching the exhaust from a motorcycle. I figured that maybe there was some engine oil spilled on an exhaust pipe, or some such. Finally, this afternoon I got fed up with the smell, and I popped the hood for a peek... sure enough, the oil filler cap was missing. Snooping around, I saw it stuck beneath the hood latch assembly in front of the radiator. So, I popped it back on, and the stink disappeared.

My question: With the oil filler wide open, shouldn't the engine computer throw a code? It didn't. Seems to me that at least the PCV system should show a failure.

Thanks for whatever help you guys have...

 

Don't think there is a PCV monitor system, so no way to set a code.
And since oil filler isn't a vacuum leak then no Lean code