From left to right my readings are:

(97 Mitsubishi Eclipse Spyder GST)

100
90
100
90

I'm fairly confused on these readings, I'm not sure how to determine if these readings are throwing up a red flag or not, I'll be honest to say I've never done a compression test before.

Can someone tell me what I should be looking for? What's an ideal reading?

 

those numbers are way to low. Are you sure that you did the test correctly and that you had a good tight seal on the tester. Also you made sure to turn the motor over enough revolutions to get the max compression.

If you did everything right then you are well below the service limit (meaning that engine is really worn out). You may want to try a wet test. Add a little cap full of oil into the cylinder and retry the test. If the numbers improve then its the piston rings that are worn.

 

I bought a new compression tester and ran it again, it was 170 on all of them, how does that sound? That's without a wet test and with the car warmed up.

Thanks for the help

 

ah ha, yes much better. Nothing to worry about now.

 

Great! Thanks a bunch