what could have cause the problem? i am buying this car from a guy and he said there's no compression in one of the piston.
i pulled out one of the plug wires out and it looks like dusty, when i pulled it out there's like dust at the end of the wire.

 

the only thing i could think of was he was running with out a filter. cucked up some dirt. did you check all the compression?

 

no, i am taking his word as of now, cause he lost the key. So according to what he said, no compression.