1993 non turbo 300zx i need to know what is acceptable compression now i have 95-105 on all cylinders car needs an injector and front main seal it has 142000 miles should i repair or be looking for another motor
Stock engines (no radical cam) should be at least 140. Squirt a little oil in each cylinder. If that makes the #'s go up it’s rings.
The compression test needs to be done when the engine is as near normal operating temperature as possible; otherwise, the test will be invalid.
This is a short review of the car: http://consumerguideauto.howstuffworks.com/1990-to-1996-nissan-300zx.htm
That, and it needs to be done correctly (throttle plate open, all plugs out). OP, was it done correctly?