How often?
 

Does it happends that you get exhausts escaping trough head-gasket?

Car: 81' 930

Problem: Exhaust leak (?) that gets louder when i step on accellerator.

I was having this slight "blowby" sound for a while...i tought that it was just a header-gasket so i drove the car a bit more before service. It suddenly become much louder. One of headers has a missing nut (on the same side that noise is comming from). I called my mechanic and he started telling me horror stories about probability of head-bolts snappping off so exhaust gases start leaking between head and cylinder. He also told me that it's fairly unusual for header gaskets to leak beacuse there is a pipe between headers and heads.

How bad is all this? Expensive? Of course...i should lift the car and take a look for myself, but i can't do it right now...

Thanx!

Did you put the exhaust manifold nut back on?
The exhaust gaskets are metal and form to fit when torqued. Tighten everything back down and fire it up. With any luck this is it and you won't even have to replace the gasket.