well ladies and gents!

I probably should earn the most idiot award ever! Well let me explain.

During the last week or so I been busy workin on my lovely 1995 Ford Ranger XLT V-6 4.0L where she suffered a major vacuum leak ... which causes rough idle. The CEL lighted P0171 and P0174.

As I disassemble to where I need to replace the gaskets witin Lower and upper intake manifolds.

The culprit got in my way ... the EGR solenoid stud bolts was VERY rusted shut too Cylinder head outside housing ... it was due for replacement of EGR and its various components.

I tried every thing to loosen up that stubborn stud impact driver you name it ... it leaves me too only option to electric grind off the old stud and break away the EGR components before removing the old rusted valves cover on driver side ... I didn't care about the old EGR components cuz I already had replacements parts for those all oem and new!

anyways ... here's the issue ... I drilled it out too wide and deep so that I can change the tap from standard thread to 1/2-13 at that time and it left me with a hole .... (pic below)



and here's pic of stock hole drilled and tapped by factory



Soo here's my question ... what will come out of that hole that I created in mistake? Exhaust or Coolant?

and is welding along the side of that hole at times to times after it quenches cool ... will it help to seal the hole as well?

Thank you for your input y'all