I have a 2000 vette and it has started misfiring. code P0300. I smell gas too. replaced spark plugs and wires first. still misfiring. checked coils with timing light. all worked. now i notice white smoke i think coming out exhaust. it does smell like antifreeze to me with gas.

could it just be intake maifold or is this a for sure head gasket? if it is a head gasket is it something a regular guy can take on or do i need to send it to the shop? whats the cost of that?

 

Do a compression test.
If you have a weak cyl. then I would suspect head gasket.
If the comp is pretty much even across all cyl. I would suspect intake gasket.

Not knowing your mech experiance and the fact that you asked, I would say no, don't atempt either gasket change. Have a good shop do the work. I don't know how long to do the job but you can prob figure at least $100 to $125 an hour for labor, parts less than $50.
Prob only need a few gaskets, an oil change, and anti freeze.

The labor to do a head gasket may be almost double of that for an intake gasket.

Get a few dif estimates, you could save a couple of hun.