So I have this civic and im guessing the gas gauge is broken but when it gets to about quarter tank it bogs out and acts like its out of gas. Any Ideas? Oh and If I remove the Valve cover will oil spill out everywhere?

 

No oil won't spill out everywhere.

Maybe your gas tank has alot of sediment in the tank? When you fill it up does the needle go off the gauge?

 

Two likely candidates for the problem:
--the fuel sender unit (in the gas tank, either under the rear seat or under the trunk space)
--the fuel gage itself

Both are known to fail from time to time. Use the free online manuals at www.autozone.com and/or the factory service manuals at http://ww1.honda.co.uk/car/owner/workshop.html for the steps to remove and test each.

Removing the valve cover will not spill oil. About an inch or so of clearance exists between where the valve cover mates with the engine head and the oil sitting in/around the rocker arms etc.