Compression ZERO
 

I just bought this car for 6k assuming it would need engine rebuild. Just did a compression test yesterday. Front Rotor was close to 90psi. Back rotor was ZERO, ZIP, NADA. Does this indicate a side seal or apex seal? Or could it be either?

Zero on all three faces? Yikes. I'd say it was already rebuilt...without any apex seals.

Sounds like an apex seal has completely left as well as scoring/damaging the housing where the 3rd chamber can't make compression.

Or an apex seal went out and took another one with it, or took them all.

Sounds like my FRONT rotor.....the one that has all the little pieces falling out of it......

Either way... It has to come apart and you will know soon.

Thanks for the quick responses. I'm going to try to get the engine out this weekend if possible.

Very common, pretty much normal apex seal failure. Plan on needing a rotor and a rotor housing during the rebuild.