Do you have to remove trans when you replace the engine

Check trans or engine mount

musnt laugh here but go to the scrapper and get the right loom

Is it a manual, or an automatic? Earlier Nissans sometimes have a problem with the neutral safety switch (a device that keeps the engine from rolling over in gear or without the clutch depressed.) Generally, if their bad, they need to be a little warm before they'll start, like setting in the sunlight for a few hours.

Good Luck!

STANT REVERSE POPPET SERIES THERMOSTAT -- 195%XB0 F, A Direct Fit OE Replacement Engine Coolant Thermostat,
Thank you for using FixYa , Lee

Remove the engine light from the dash then it wouldn't light up anymore =]

You need to replace the clutch and pressure plate --your clutch is worn out. Plus other parts like throw-out bearing ,pilot bearing and may even need the flywheel machined flat.
You need to take it to a shop or if you are mechanicaly minded could do it your yourself,

1996 Nissan/Datsun Sentra 1.6L SFI DOHC 4cyl

Nissan Sentra/Pulsar/NX 1982-1996 Repair Guide
The alternators for Pulsar and Sentra have not changed much over the years. However, the 1987-88 alternators for Pulsar and Sentra have a different internal diode assembly.

1. Disconnect the negative battery terminal.
2. Disconnect the 2 lead wires and connector from the alternator.
3. Loosen the drive belt adjusting bolt and remove the belt.
4. Unscrew the alternator attaching bolts and remove the alternator from the vehicle.

To install:

1. Install the alternator and retaining bolts loosely.
2. Install the belt and connect the wiring.
3. Adjust the belt as outlined in . Torque the retaining bolts to 25 ft. lbs. (34 Nm).

I hope help you with this (rated this help).

make sure the computer has a 5 volt reference signal.

check the sparkplugs

yep they will interchange