It is like any other test. Like an EKG. It takes somebody that knows what
they are doing in order to interpret the results correctly. Depending on
whether overall compression is low or just an isolated cylinder or two would
determine the fix.

Pertaining to the other poster I have never heard of a running compression
test. In as much as connecting a psi gauge to a cylinder and running the
engine minus that spark plug. If indeed this is the case that makes no
sense because you would have a misfire with that cylinder and it would set
off codes in the computer that would need to be reset. Mostly compression
tests are just done while cranking the engine over and disabling the engine
so that it temporarily doesn't fire.

CaptainKrunch.


"ILJ" <res1kumh@verizon.net> wrote in message
news:tJYSb.8763$9a4.3978@nwrddc01.gnilink.net...
> What is the point of a compression test? I know what it measures, but if
you
> get a poor compression ratio, how do you fix it?
>
>