kroze

I finally figured out why my car was running on 5 cylinders even after replacing coil pack, spark plugs, fuel injector, and crankshaft position sensor.

It was the harness, you know the giant wiring harness going from the firewall and all throughout the engine bay

It looks pretty tough to replace and was wondering if I should just get rid of the car altogether.

litch

iTrader: (2)

A wiring harness = 1000 part, if you know someone at the dealership plus a minimum of 800 labor to pull the engine and rewire.

kroze

so I'm pretty much going to need a new car

Maxima_Joe

iTrader: (384)

You can always just run a couple new wires which would be the easiest route.

If you do decide to change the harness it can be done with the engine still installed and used they only run around $100-$200. Hardest part is finding one that will work with your car.

If you've seen the write up for the heater core replacement then that's practically what you'll need to do to get the ECU plug through the firewall.

kroze

It is just one wire and that's the trigger wire for coil pack #6

I traced it up to the valve cover and unable to go further (near the firewall).

Most likely it is the bend near the strut tower that cause it right?

Maxima_Joe

iTrader: (384)

You will want to check for continuity from the ECU pin to the coil pack pin. If there's no continuity then just run a new wire.

mrjasonlyrics

Dude if you mess up that wiring it will cost you a great chunk up change. Don't mess with that unless you know how to do it, and believe you me it's strictly a dealer part and it's very expensive. One of the most expensive small things you'll ever have to buy

kroze

How do I check it from the ecu pin? I could only managed to trace from the coil pack to the valve cover of cylinder 2, 4, and 6. Do I have to take the ecu out to in order to check the continuity?

Maxima_Joe

iTrader: (384)

It sounds like your checking the rear bank Closest to the firewall? If so that's cylinders 1 3 5.
No you wouldn't have to take the ECU. You can get at the wires on the passenger side. You would have to extend your wires on your multi meter though.

CMax03

iTrader: (3)

Did you open up the harness? Have you tested the lead all the way back to the ECU to ensure it's the injector wire.....Have you tested the injector plug for power or ground?????? Or you just posting without testing anything!!!!!

kroze

Each plug that goes to the coil pack have 3 wires (power, ground, and injector/signal)

I tested each and every individual plugs that goes to the coil pack and only the plug that goes to coil pack #6 doesn't work. I used a test light to test them. There's power and ground going to coil pack #6 but the signal wire barely light up the test light. Which makes perfect sense because it correspond with my CEL code P1320 & P0306 (misfire cylinder #6)

I managed to opened the harness all the way up to where it sit right on top of the valve cover where Cylinder #2 is and there's very little signal coming through.

max ride 41

iTrader: (4)

so, get a mechanic/shop that specializes in wiring /electrical issues and get an estimate. you don't want to short something out or put an incorrect gauge wire in there. i know its not rocket science, but be safe and watch what your doing if you do it yourself. gl

89newporker

I am tracing the same trouble code on my 1995 SE only with P1320 which tells me that there is a fault in the ignition primary circuit. I was able to snake the harness out through the firewall without removal of the dash. it is tricky but it can be done just be gentle with some the connectors. I Have a misfire in cyl 5 and cyl 1 with no other trouble codes How the hell am I supposed to trace the fault when the Harness passes inspection both physically and with continuity? I pulled the car in for service and she was running beautifully before now after servicing she is missing? WTF? I JUST replaced all 6 injectors with new OEM units "JECS" stamped in the casing and all six coils with 6 new OEM units they all have Hanshi stamped in the casing and all are matched sets. I am about to lose it with this car. everytime I repair something; something else craps out and I have to fix that as well. THIS is getting expensive guys and I am not willing to just throw money at it "hoping" its going to fix it. the bloody parts already cost twice what my toyota costs me and I am about to push it off a cliff and call the insurance company just to be done with it. I have power to the coils and grounds are in beautiful shape including power to the injectors and even getting a a signal reference from the computer for the injectors. CkP has been replaced with the silver dot issue as well as the CPS sensor! SHE runs like a dream when she is running correctly, and I am NOT about to suspect the ECM because "ecm's" just don't go out without something causing them to go out. The Ckp Ref sensor is Nissan Fare as well Thoughts?