Camaro engine trouble

i have a 1991 3.1 v6 camaro and i have been told that it either has a blown head gasket or a blown intake manifold how can i tell which one

We need to know more about the symptoms the motor is exhibiting? Not enough info to give you any kind of a good answer.

Bad head gaskets often get oil in the coolant, or coolant in the oil. Not sure what a blown intake manifold really is? A crack in the intake manifold or a bad gasket allows more air into the fuel mix for one or multiple cylinders which can cause running problems.

None of this is really helpful until you tell us more about what is going on with your motor.

well i think there might be coolant or water in the oil because there is more than what is supposed to be in there but it doesnt look milky or anything

and when i take the spark plugs out it will run fine for about five minutes but then will run rough until its so bad it dies then i have to clean the spark plugs again

i had it tool to a mechanic and he replaced the computer and drained the gas and cleaned the spark plugs and then it would run fine for 5 minutes and then he would have to take the spark plugs out and clean them. and when he took some of the gas out and burnt it it had a oily residue. but i do believe there is either coolant or water in the oil but i dont know for sure

and the motor when its is running has alot of git up and go lol even when it starts running rough but it will die if u let the rpms down when its running rough. i really need some help and anybody can ask me questions ill be here for a while cuz i need help

What is fouling the plugs? If it is oil, then it isn’t a head gasket. And you don’t get oil from a bad intake manifold either. Oil either from bad rings, or leaking down the valve guides from the cylinder head.

I think you have a very sick engine that might need a tear down and rebuild to find and resolve the problem. But that is the worst case scenario, let’s see what others have to say.

well the car doesnt smoke at all it just after about five minutes after cleaning the plugs it starts running rough … and i dont know if its oil or if its water on the plugs but i think it might be water. what would cause that?

i have no idea what might be fouling the plugs but its either water or oil but i will find out tomorrow because i will try to check the plugs for rust cuz its been sittin for at least 3 weeks since i got it back … im also going to check the compression on it tomorrow … any help would greatly appreciated THANKS …

i really need some help on this one

Run a compression test. This will tell you whether a head gasket is breached into one or more of the combusion chambers.

If the compression is fine then you can at least assume the fault is with the intake gasket. With the intake off, a careful examination of the surfaces and gasket should reveal the problem.

You should not operate the vehicle with coolant diluted engine oil as that can destroy the entire engine.

you could think about pressure testing cooling system with the plugs out and watch for which hole coolant pours out.

im getting a compression test on it today. but can i take the oil plug loose a little bit to find out what is in there?

Removing the oil drain plug will only reveal what the engine oil looks like. Generally what happens when coolant and engine oil is mixed in a running engine is that it becomes a milky or tan appearing sludge. Not good of course and can be harmful to the engine depending on how long that has been going on.
About all one can do is change the oil and pray.

You might post the compression numbers for discussion. Tt’s surprising how often lousy numbers are interpreted as good, even by some mechanics.

how is the coolant or anything else getting into my oil? how would coolant get in the oil? … and how would water get into my oil?

Coolant can dilute the oil from either a faulty intake gasket or head gasket but based on what you’ve stated I don’t know that either one is the problem.

You state it runs for 5 minutes before apparently loading up and dying along with fouled plugs and a gasoline oily residue. This could be due to a leaking fuel pressure regulator, clogged converter, or the gasoline itself. Sometimes gasoline becomes diluted with diesel, solvents, etc. it can take on an oily appearance along with making a car run poorly or not at all.

There’s not enough info known to make any kind of reasonable guess but I’m always a bit antsy over someone replacing an engine management computer.
If an intake or head gasket fault is suspected then connect a vacuum gauge. That can be done in seconds and will also let someone know if there is a problem within seconds.

well i know it not the gas because the mechanic put new gas in it because the old gas that was in it was bad but i think the cause of it was because it set for like almost 7 months with the same gas it it. i think that was the reason for the bad gas in it when i took it to my mechanic.

and the reason he put a new computer in it was because he had checked everything else and narrowed it down to something like the drivers or something in the computer was bad.

now about the fuel pressure. before my car completely died near the last of April i would get it out on the road and the road has a very very slight incline and when i got the car out on the road i mashed it to the floor and it didnt hardly go anywhere but it eventully got up to speed and woudlnt hardly idle and when i had to stop i had to keep my foot on the brake and keep the rpms up to even keep it running. now fast forward about 7 months and im getting it back from my mechanic with it running but like i said only for a little bit then it would start running rough but when i got it back from the mechanic i got it out on the road and mashed it to the floor again but this time it got up and got to speed quick… but when i bought the car back in the first of April (yeah it run fine for about a whole of maybe three weeks) i took it to the rods runs that we have up here in Severville Tennessee and it run like a charm and you couls be rolling at like 5 mph and floor it and it would fishtail (3.1 v6) lol…

but ask any more guestions and thanks for all the comments already and i hope i get more so i can fix my car THANKS