Montana 2000 knocking and smelling

Hi friends
I have Montana 2000.
I have problem with knocking and smelling of engine and I have just 94,000 miles.

Someone can help me with advice
Thanks
Edgar

what kind of smell, gas, exhaust, burnt wiring, etc... and is the knock just at start up, after start up or all the time.

what kind of smell, gas, exhaust, burnt wiring, etc... and is the knock just at start up, after start up or all the time.

Actually , i didn't check what kind of smell . The knocking just for ten first minuts and after the enginee warmed up the knocking disappear.
Thanks

this is most likely an intake manifold failure. GM Dealerships see many of these a week and GM has published 2 service bulleins on this (03-06-01-010B & 02-06-01-014