Electrical issue?
 

So last week I bought a, new to me, used 2005 Hyundai Elantra.. :D
This week however :mad:. Sharper minds than mine are required on this one I admit I'm over my head.

The vehicle ran fine for two days after I bought it, then the CEL came on, I took it and had the code pulled. It's showing p0420, catalytic converter issue, however other than the code, there are no other symptoms of a cat problem.

Someone prior to my purchasing it, has ran a ground wire from the negative battery cable, over against the engine block, what for I don't have the slightest clue. I did get one mechanic to take a look at it, he just said from what I'm describing it sounds like an electrical problem.

At this point, the vehicle will usually start up fine, and run great for maybe 15 mins, then it dies suddenly. I can fumble with that wire as pictured, and it'll start up again, and run a few more minutes etc etc and the cycle repeats.

I'm over my head on all these electronic gizmo stuff, I was hoping wiser heads could offer a suggestion or two. Thanks so much.

I suppose I can take comfort that everyone is as stumped as I am.. LOL

Well with any luck maybe I've found my own problem.. There is an electrical plugin on the top front of the engine that is cracked on the outside, and broken apart on the inside of the connector. The two contact wires rotate freely when they should not.

See pic... Can anyone tell me what this connector goes to?

There are actually 2 things there. The Oil Control Valve (OCV, #12 in the pic below) for the CVVT (Continuously Variable Valve Timing) and the Oil Temp Sensor (OTS, #15 in the pic below).

https://www.hyundaitechinfo.com/data...G/efke301z.gif

https://www.hyundaitechinfo.com/data...G/efke301b.gif