The gauge will hold peak pressure if it is the type designed to do
so. If such, it will have a release button to zero the gauge.  It not
it will register the pressure it sees. You have to watch it and read
peak pressures. In the case as described (dropping pressure) that
would indicate either leaking valves or worn rings.  Do a dry/wet
pair of tests on each cylinder. (test dry then squirt some oil into
the cylinder and test again.) If a noticeable improvement you have
worn rings, if not, leaking valves.Date:    Fri,

16 Nov 2007 08:26:12 -0800
From:    neil N <musomuso@GMAIL.COM>
Subject: Compression tester question

Hi all.

I bought a compression tester and tried it on my parts van 1.9 WBX
engine. On two of the cylinders, the gauge would drop while still
threaded in sparkplug hole.

I was doing this w/o remote starter.

The gauge should hold its' reading right? i.e. once it's pumped up, it
should stay there correct?

It was threaded properly, and adaptor to hose was threaded properly too.

Apologies for such and elementary question!

Neil.