I have an 87 D21 Nissan truck it will start and run but just a second then stop firing you can leave it over night and it will crank again. I have changed the coil got the same thing. I checked the voltage to the coil with switch on its 12.95 volts when turning over it goes down to 9.5 volts. any suggestions ?

Need three things for gas engines fuel, fire, vaccum. Do you have fuel, fire, and vaccum could be injectors should register 1.8 each could be fuel filter, plugged, could be bad vaccum broke, cracked or missing. if it only runs for a second do you lose fire, or fuel?? If you lose neither could be vaccum.

CHECK RESISTOR TO COIL FOR OPEN CIRCUIT. KEY IN START POSITION BYPASSES RESISTOR, JUMPER WIRE ACROSS RESISTOR WILL CLOSE CIRCUIT ALLOWING MOTOR TO RUN FOR TEMPORARY FIX. THIS BEING THE CASE FOR MANY CARS

You ever get it fixed if not try checking the distributor shaft it's two pieces wiggle the rotor and see if it has play mine did the same thing,till it got real bad then the rotor moved about a quarter of an inch no one even knew it was two pieces,it ran good for about a year,now it's skipping w/o power, once it warms up. The temperature gauge moves off the white mark it skips with no power. Any ideas

Had top replace the fuel pump on 1990 d21 for similar reasons. Also fixed fuel gauge nor working

On an 87 V6 , crank angle sensor in the distributor 95$ whole distributor 160$ controls air, fuel,distributor advance. If its f'd up it reads all messed up and shuts down..I bought one installed it and saw that the bearings were missing the separation cradle and the 5 bearings were all together on one side. So I had to then buy a new distributor. Check your bearings by pulling straight up on the CAS after removing the 2 screws. That's what happend with mine and it ran fine till i got the new dist.