It isn't the intake manifold, it's the intake gasket.
For now, just make sure you NEVER have Dexcool more than 5 years old.
If you want to proactively replace the intake gasket then that's fine (I would do it if it was my car), but at the same time you should install some pipe plugs in the coolant channel that goes to the throttle body (to prevent it from freezing).
It is a pretty straightforward job. If you want details on the pipe plugs, let me know.
Then in the future, you should drain and fill some antifreeze every year, which will keep the coolant from tuning into the acidic crap that has probably ruined your gasket.
-BC
Bookmarks