From the category archives:

FAQ – Nissan 300ZX (Z31)

The manual says to remove the timing belt and the backing plate to do this, but here is the easy way: First, locate the sensor, it is on the front face of the driver side head. Hard to see sometimes, look around. Remove spark plug wires from distributor cap and disconnect temp. sensor(this takes some [...]

NOTE: There is no need to change your injectors. Nissan has recalled all 84-89 300ZXs in the USA and will replace the injectors and some other associated components free of charge. Make an appointment with any dealer if your car has not been done yet. If you’re unsure whether your car has been done yet, [...]

Without a doubt, the easiest way to pull or replace the engine in a Z31 is with the tranny attached firmly to it. You can probably accomplish this method in about the time it takes just to drop or install the tranny if you were going to do them seperately, plus you don’t have to [...]