This truly depends on the engine type. Some engines have very flat intake manifolds and a bolt can simply sit. However to err on the side of caution you should assume that this "small" bit could go into a valve. This would mean a bent valve or at the very worst it would travel all the way to the piston resulting in certain bore damage. Try a magnetic probe or , if you must, remove the manifold.
The starter is located under the intake manifold. You will have to remove the intake manifold being very careful not to drop any of the bolts into an in port. The starter is fairly easy to access once the manifold is off.
You can't just drop new bolts in the holes where the broken bolts came out of. The manifold has to be removed and the broken bolt ends removed with an EZ-Out or at a machine shop. While the manifold is off, you can take one of the bolts to an auto parts store for match-up and buy the bolts you need.
The air movement that creates the negative pressure (vacuum) is being redirected to the intake manifold to serve engine acceleration - making the vacuum drop.
Does the heater work when you go down the road and stop when you come to an idle? If so, I had the same problem several years ago with my 1993 mercury villager. The water level is too low. Although the radiator appears to be full, you have to bleed the system. On the top of the intake manifold (Center) there is a small bolt that needs to be taken out. It's very hard to get too and don't drop it! The bolt is above the radiator level but if you don't remove it you get air trapped in the top portion of the manifold and hot water doesn't go through the heater coil. With the bolt on top of the intake manifold removed, start your engine and slowly keep pouring water into the radiator until water comes out the hole where you took the bolt out. Put the bolt back in and tighten it up.
extremely difficult without removing the engine. i have seen some drop the engine down about a foot by disconnecting the motor and transmission mounts & did not disconnect alot of lines and were able to change the intake gasket.
It is easier to remove the upper intake.
I believe edelbrock makes a selection of intake manifolds for the 4.9. I have a carb 4.9 in an 81, I'm thinking of getting one.The 301 (4.9) Pontiac was pretty much a one off engine. To date, I know of no one that makes any type of performance intakes for it. Most people rip out the 301 and drop in a 350, 400...whatever.....since it will bolt right in. The only options you have is the factory 301 4bbl intake......or going to the T/A turbo unit.
Start with removing the intake manifold. If it still not found you will have to drop the oil pan. If it made it's way to the bottom of the oil pan it would be harmless, but you will not know.
you need to drop the exhaust from the catalitic converter to the end of the exhaust manifold. then loosen bolt from oil pan connecting starter. undo positive cables and repeat backwards for instation
First you start by taking the air filter off. Then unbolt the carb itself. Then you will see eight bolts that are bolting down the valve covers, remove those and next the covers themselves. This will enable you to see the bolts easier. Around the outer edge of the intake manifold you will see 3/4'', I believe, bolts. Loosen all of those and remove them. After that remove all hoses from the intake manifold. The manifold should now come right off. You might need to wiggle it a bit to loosen it but it will come free. And that's it. Be sure that upon removal of the old gasket you take a razor blade and scrape off all the old gunk. This will make for a better seal. Be sure not to drop anything into the block while you have the manifold off.
Engine manifold vacuum should be between 15 and 21 inches of vacuum, the reading should be steady at idle, when the engine is revved and held the vacuum will drop then stabilize to 15-21 inches. The vacuum reading should be taken from a port after the intake butterfly. A Vacuum reading can be a helpful tool for diagnosis especially onvehicles prior to 1996 and OBD2, with OBD2 the computer does a lot of the diagnosis for you.
Nothing 'happens'.