paulh634

Vehicle is a 1990 300zx N/A
Cylinder 2 has no spark, all other cylinders fully functional.

Narrowed down to wiring by testing with multiple coil packs/spark plugs grounding on intake manifold. All coils/plugs work on all other cylinders, however no spark on cylinder 2.

2nd Generation PTU, have verified via resistance testing in FSM that this PTU is within spec. From my readings I don't believe the PTU would cause a single cylinder to not spark, although I believe this testing should rule this out either way.

Tested connector to coil pack:
a has continuity to ground,
b has 12v,
c has continuity to PTU.
***(a,b,c referring to the labeling of coil connectors on diagrams located on EF&EC 119 of FSM)***

Cleaned all connectors to PTU and CAS, all seem to have no corrosion and be in good condition.

I do not have a way to measure pulse to the 3rd contact on the coil connector (contact c), I've gone through the troubleshooting on EF&EC 119 diagram d in the factory service manual and have continuity between connectors 1-6 on the PTU and their corresponding connections on the ECU (1-1, 2-2, 3-3, 4-11,5-12,6-13).

I'm assuming in step E that the pin 21 is the ground pin on the PTU connector (all the way to one side, next to white wire), and this does indeed have continuity to ground.

What am I missing here?

NismoPick

Welcome to ZDriver!

The easiest method is to swap coil packs and see if the problem follows. If so: dead coil pack.

paulh634

Please read past first sentence...

Thanks