I'm thinking this is a dumb question, but is there anything magic to getting a mazda compresison tester to work? The motor is making compression (I can hear it) but when I hook up the tester and turn over the engine it doesn't read anything, RPM or compression.

Is there anything obvious I'm missing?

I did just purchase it, but had verification that it works and I don't doubt that... so what am I missing? I'm going to try tightening the pressure sensor in the engine.

Yes I'm using the leading holes, and the tester does have an Oring for sealing on the housings.

TIA

 

Don't Laugh but Ive seen guys take both leading and trailing plugs out try then check compression. I'm sure you didn't do this...?

 

http://www.fd3s.net/compression_test.html


hope this help