Methanlol lifespan

Has anyone experienced problems with methanol that has been in storage for about a year and a half? My car is harder to start then normal, using alot more fuel even just to warm up, fuel has almost no smell, almost no fumes out of the headers. Some say that methanol is chemically stable but just absorbs water, some say that it loses its oxygenation. My fuel is only stored in the original drum with bungs tight, in a dry shop but does have major temp variations. Feedback Please!

If it’s sealed airtight it will last a very long time and openings to the air it will suck up moisture very quickly

Methanol is a chemical (CH3OH). It doesn't magically fall apart or become something else unless it's contaminated.

pour alcohol into clean container, if it is cloudy or has "floaters" in it
then it has moisture contamination
It will make starting engine more difficult and will be off up to 20 percent on power
all it is good for is killing weeds after that

Methanol sucks water out of the air and does what others have already said.

There are a number of possibilities.
First. How ave you stored it....was it stored in a lined steel sealed container...was it stored in an unlined steel container...was it stored in a pastic jug...
If stored in a sealed lined steel container it should not deteriorate for a longtime.
If stirred in an unlined container it ay interact with the container and loose one potential energy, usually not but possible.
If stirred in a pastic jug you run a risk of the methanol interacting with the chemicals in the jug plastic...colored jugs are the worst...clear and light blue less likely.

You can check it with a hydrometer....you need to find a temperature reacted specific gravity chart and take the temp of the methanol and then read the specific gravity around .795 plus or minus depending on temperature.
Another test is the water test....take a small amount of methanol and mix with equal amount of distiller water ...good methanol will stay perfectly clear...milky means it has hydrocarbons present and not up to full potential
Also a third test using gasoline will detect water in the methanol....should be able to find procedure on Internet .

Been testing methanol for motorsports events for 20 plus years.

As entwined by others methanol is a moisture magnet....

Water present in methanol will change the specific gravity very quickly. A graduated cylinder with methanol and a hydrometer in the methanol will rise as water is added.