Editing Z31/Rewirefuelinjectors php

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== Z31 Re-wiring your fuel injectors ==

The "Service Campaign" done by Nissan to all 84-89 300ZX's re-wires the fuel injectors to fire purely off the leads for only two of the injectors. It is speculated that Nissan did this to save on labor costs when the campaign was performed. What this effectively does is alter the firing order of the injectors so all 3 injectors per side fire at once (batch-fire mode). Now, there are really only two injector drivers in the ECU. The stock configuration is a batch-fire mode anyway, but wiring three injectors onto one lead both changes the firing order and shortens the overall wiring used. A harness exactly like this one is used to connect 3 injectors to one lead:

''WARNING'' - Do this diagnosis/mods at your own risk. We Are not responsable for any issues of your own doing.

=== Parts and tools needed ===

* Wire strippers
* Electrical tape
* Heat-shrink tubing
* Soldering iron and 60/40 rosin core solder

=== Process ===

* Disconnect the battery. Safety first!
-
Remove the electrical tape from the harness segments on either side of the intake plenum.

Tip: The tape is usually sticky and nasty from heat. The best removal method is WD40 and an old rag. -
Locate the four additional leads that have been clipped and covered in heat-shrink tubing.
* Cut the “dealer installed” harness so that you have enough free length to reach from each injector to the original leads. Leave some slack for flexibility.
* Remove the heat-shrink from the original harness leads, then strip back the insulation.
* Tin the wires with solder to prep them for joining.
-
Solder the wires together according to their color/function. Make sure your joints are strong and fully soldered.
* Slide heat-shrink tubing over the joints and shrink with a heat source (heat gun, lighter, etc.).
-
Re-wrap the harness with new electrical tape to protect your work. Duplicate this process on the other side.

=== Sources Used ===

[[Z31/z31fsm php|1984-1988 Nissan 300ZX Factory Service Manual]]
* Writen by: Jason Butts -AKA- Jason84NA2T

[[Category:Imported from Xenonzcar]]