I just purchased a very clean 2004 Sebring Convertible Touring with 46k miles.

Been going thru all the maintenance and repairs, when I discovered small holes next to 3 of the 8 intake plenum bolts. The appear to be random sizes approx 1/16"
Not sure if the plenum is defective, and if they are lending to a slight vacuum leak
Using a rubber hose as a stethoscope, it sounds like there might be air entering the intake air stream.
This would effect the 02 and MAF sensor readings if these are indeed small vacuum leaks.
The engine runs nice, however I've seen cleaner plugs in my 02 Sebring with 144k miles.

Anyone ever notice this and look into it?
Very strange.

 

never seen them on mine, but then never looked for them. they could be drain holes to let water out if it gets in there.

 

Drain holes would kind of make sense...but they're only at 3 of the 8 bolts, and there is no place for the water to drain too.

Also looked at my 02 and there are no holes.

 

left-to-right is passenger to driver. top and bottom would be flipped. can you highlight which 3 have holes?