99 grand am gt 3.4 no compression on either the 5th or 6th cylinder and blowing exhaust out of the intake. Any suggestions??? please help!!!

Basic theroy of a gas engine Suck Squeez Bang Blow!
Intake (suck) compression (squeez) Spark (bang) exhaust (blow).
If you have gas! Check if its getting into cylinder (suck). Check your compression (squeez). Check your spark (bang). Check your exhaust (blow) make sure no restrictions! Sorry no easy answer!
MUST TEST.
Good luck

head gasket blown or warped heador cracked head on engine

Put #3 cylinder in firing position then put air pressure in that cylinder and remove the oil cap. If air comes out throttle body the intake valve is leaking. If air comes out the tail pipe the exhaust valve is leaking. If air comes out where the oil cap came off the piston is leaking.

or you getting the right fuel pressure? check fluid filter, check pressure regulator, check spark plugs to see if they are soaking wet if they or wet take them all out and pull fuel pump relay out turn engine over and blow all gas out the plug holes. install plugs and relay and try start again , check engine compression, check coolant senor ,check cam sensor

well thats good. if you put in oil and there is compression that tells you that your rings are bad and neeed rebuilt. i would check your timing, its possible that the exhaust or intake valve is open on the compression stroke letting the air escape.

I would suggest that you have a blown head-gasket. The Z24s have a tendency to blow the head-gasket between #3 & #4 cylinders. I would do a compression check. You will probably find low or no compression on those 2 cylinders.

Is this a quiz? Each cylinder contains one piston that takes four strokes to coplete a a full cycle. the intake-down,compression-up, power-down, exhaust -up.
A two stroke has up and down only . Compression and power Now, I thik you really meant the firing order. I'm not sure but Would make sense 2-3-2?

If it's dead in cylinder one then it could be a burt valve to find out for sure all you do is put it up on top dead center of the compression stroke and pull the spark plug out and apply air to that cylinder, You can remove the air cleaner and the radiator cap so that where ever the air comes out thats where your problem is, if it comes out the intake its the intake valve if it's comming out the exhaust pipe its you exhaust valve if it blows bubbles out of the radatior then it's the head gasket, if it comes out of the rocker arm cover then it's the rings.

here are the common causes of a missfire, defective ignition coil or ignition coil wiring for that cylinder, defective fuel injector, defective powertrain control module, intake manifold vacuum leak, low cylinder compression.

your cooling system is preasureising due to a leaking cylinder head gasket the white smoke you see is coolant passing through the exhaust valve on the offending cylinder have the cooling system tested for CO content hope this advice helps