Nissan Injectors....what gives ??

[Ed]

At 12:09 PM 2/26/97 +1100, you wrote:
>I've just spent the last few days doing a complete wire trace (several
>times !!) for the newly installed aftermarket injection system on my
>Datsun.  The reason ??even though... the computer says it is getting an
>RPM signal (via a crank trigger indicating TDC) there was nary a peep out
>of the injectors.   I thought maybe the injector drivers had died.
>
>Now, almost by accident, I've found the likely cause of the problem.  I'd
>been advised to use 'ballast' resistors in series with these injectors as
>they are from an early 80's Nissan L28 engine and that's what Nissan did in
>those days.  I was told  the injectors wouldn't work properly without them.
>In a last desperate act to get the engine running, I  bypassed the
>resistors to power the injectors direct - lo and behold,  the engine starts
>and runs beautifully !!
>
>Can anyone shed any light on this ??.  The injectors show a resistance of
>2.5 Ohm in each case, which I'm told means that they need to run with the
>ballast resistors, but are there exceptions to this rule ?? (it seems that
>I have one !!).   Am I risking damage to my computer, injectors or anything
>else by doing this ?? (ie running without the resistors).  BTW, the
>resistors are off an engine of the same period and checkout OK.


Check the resistance of the injector series resistors.  They should be 5-7
ohms each.

LE/LH/LU injectors had a high internal resistance without the series
resistors.  Between 2 and 3 ohms resistance for the injector itself is normal.

As for the computer question, I'm not sure.  I'm just getting into this stuff.

Good Luck


Chief
Gainesville, FL