Thread: UPDATE:::cylinder 3 will not fire :(

I am facing similar problems, my AAC is under voltage with ignition off.

so while i was cutting the loom/tape from the harness, about 5-6 inches from the dizzy plug, the plastic on the solid blue and black with white stripe wires was split and what is that silver wire twisted with those two wires for? its just hanging out in there with them.

there is this aluminum type tape inside of the cover protecting them. does that go anywhere?

That sounds like shielding for the ignition signal to the ECU.

what does that wire do tho? it doesnt have a place to go...its just hanging out inside the harness. that silver wire was making contact with those two wires that were split open so i fixed that, and put the harness back into the car and now the fuel pump isnt priming.

i know what the issue is with the fuel pump. I had to fix a wire on one of the underdash plugs and it came loose so i will fix that tomorrow and hopefully i just figured out what has been causing my nightmare of a problem.


does that silver bare wire go anywhere?

Go into your EC PDF file for the 1996 sentra, and skip to PDF page 312 (EC-84)

Voltage check the entire list, first.

Then go to PDF page 375 (EC-147) for distributor checks.

To make it even easier, here's a diagram I put together really quickly using the FSM.

going out to the garage to do these checks

ok so on pin 4(eccs relay) it has 28vdc at idle, ignition signal pin 1 has only .2vdc at idle and the ignition check pin 2 has only .2vdc at idle....thats below the fsm standard.

pin 40 camshaft position signal is under standard(.3volts ac) and 44 for the other camshaft position signal is at 0.00 volts ac.

also 41 and 45 are the other camshaft signals and they have 5 volts(over the standard)


Ok so basicly im finding that i am getting no voltage from the camshaft positioning sensor and over voltage on the other part of the camshaft signal. isnt this inside the dizzy? i hope its just broken wires in my harness or something.

does the b13 ecu use that signal? blah

whats my problem guys? bad ecu? bad harness?

This is bad. You should have 1VDC MAXIMUM, once you start the car, and the ignition circuit is disengaged. When the vehicle is off, and your key is not in the ignition, what voltage do you get to PIN 4?

Pin 1 with a voltage shortage means that either the transistor in the Dizzy is bad, or you have a bad ground.

Pin 2 should have 12VDC, so you're seeing no voltage to pin 2.

Are you grounding your multimeter to Pin 43 (ECCS GROUND) on the harness?




They should both read an identical voltage. They are tied into pin 3 of the distributor harness. Ohm out pin 3 of the distributor connection to the pin 40/44 of the ECU harness.



Check wiring by ohming out pin 4 from distributor connection to ECU harness.



Won't know whether it's a bad ECU or Harness until you check like I mentioned here. Yes the B13 uses this signal. The cas disc is what is being referred to as the camshaft pos. sensor.

balls, give me a little while and i will be back with what i find. Thanks cliff

Figured I'd clarify on the cover you're referring to. It's a grounded shield to help protect the signal wires inside from outside interference. Think of it as a "signal cleaner".

Also, while I'm thinking about it...

Do you have both ground reference wires connected to the intake manifold? There's 4 wires total, and their crimped in pairs to an eyelet that bolts to the intake manifold, usually on the top or back depending on your manifold. (lowport on top, highport on "back").