I want to put seafoam into the intake mainfold
Do i have to remove the mass air flow sensor first?

 

If you put Seafoam after the MAF sensor then no, do not remove.
If you put it in before the MAF then yes, it must be removed.

 

Can i drive the car with out the map or mas air flow sensor would it harm the car if it ran with out it?

 

Can we inquire as to why do you want to use the seafoam in the first place?

 

I hear engine noise i want to clean carbon build up around the piston rings

 

Before getting involved in something that may not correct the noise problem, it would be better if you were able to pin down the area where the noise appears loudest.
Carbon around piston rings doesn't usually make any noticeable noise.
Do you hear the noise when the engine is hot, cold, idling, at some particular engine speed?
Is it a tapping noise, knocking noise, heavy rumble type noise ? As you can imagine moving parts do make a certain amount of noise which lubrication usually helps quiet them down.
Also, if excessive clearance is a cause that is another possibility.
How about a little more details on when ,where and under what conditions you hear the noise in question?

 

Cold engine start
I want to use seafoam to ckean any carbon build up in my engine
I like to maintain my car
Its a 2009 accent and looks like the previous ownet did nothing to it.

So i want to clean valaves and clean all around what ever i can do to bring back performance and hp loss

 

When cold the oil is thick will take a while to get up to where it needs to be, so did you consider changing the oil , use the recommended type and weight (like maybe 10W30 if that is what they recommended)Then comes the filter. Some filters are not of the best quality and for the first filter consider a Hyundai filter. A good quality oil and filter can do wonders for a good oil change. I am just hoping I can save you some trouble. If on good advice from a reputable shop the product you are planning to try was recommended that decision is up to you. What kind of performance loss is taking place?

A side note, a tankful or two of premium grade gasoline can help .

 

I did oil change recomended quaker state 5w20 is recomondes in the book manual and on the oil cap.

But i want to try to put 0w20 full synthetic

I am using vpower shell this is my second full fill up. Since gas is cheaper now i figured why not go vpower

But again there is definet loss of hourse powet no doubt about that.

I did chevron techron 2 fill ups ago

For that reason i want to clean the vavles and engine using seafoam into my throttle body but i am afraid to run my engine with the MAP sensor pulled out

 

Maybe a little guidance,

If your MAF sensor was disconnected the powertrain system is supposed to resort to "default" settings to at least allow the engine to keep running. Of course you should get a check engine lite.Not supposed to disconnect any sensors with the key on !!! Not being able to hear/see, feel the engine run, not a good idea to suggest something that may not help and if anything make things worse. Take for instance, if there was a small amount of carbon around the piston and rings , once that is removed , if it was helping seal the compression in the cyl and now the gap is increased, it could cause lower compression and possibly loss of power. If the rings are stuck and not sealing well, that could cause loss of power too. Going to such a low viscosity motor oil on an engine with considerable miles could be asking for trouble with low oil pressure. I realize you have good intentions, but I would suggest you do a lot more research before attempting to correct some problems with just a "Band Aid". Again, this is your choice.