How do you time a 240sx?
With the engine off, look around the crank pulley (the big one
with 2 or 3 belts at the bottom) towards the upper left of the
pulley there is a pin sticking out of the engines front cover,
clean it, we will use this to time the motor. Clean the rim of the
pulley as well, you may notice some white lines etched into the
pulley make sure they are extra clean.
Next attach a timing gun to the battery and to the No. 1 spark
plug wire making sure all wires are placed in a way that they can
not get caught in the fan. Then loosten the two bolts holding the
distributor to the motor.
If your reading this I'll assume that the car will not start or
it runs sluggishly so have a friend hop in the car and crank it for
you (only crank, pumping the gas is NOT needed). So while he (or
she if your lucky) cranks the car look with the timing gun at the
pin we cleaned earlier, when the timing gun flashes you should see
little white tick marks on the pulley count from the left 5 marks
now turn the distributor until that mark lines up with the pin. Let
the engine warm up.
Once the engine is warm you need to unclip the throttle position
sensor. If your having trouble finding this stand at the front of
the car and look on top of the silver pipes on the left. There
should be one or two thick black cables heading down toward the
front of the engine and end at the throttle body. There should be a
wire with a gray connector coming out of the right side of the
Unplug the gray connector. Now rev the engine up to 3000rpm
several times, check the timing with the gun and line up the marks
on the pulley to the pin like before. Tighten the distributor and
check the marks one last time, then plug the gray clip back in.
DONE! (note: there's another connector with many wires (12+) near
the throttle position sensor's connector, this is not the right
one, leave it alone)