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Just popping my head in to give others some idea to my problem, in the case that it could be happening to you.

First things first, like my post in the DIY about tie rod ends, make sure you get permission by your misses to play with your car. On this day I was lucky, she wasnt around. I actually decided to look into this for motivation to do my uni study and it worked... lol

If at the end of this I have fixed my problem i will try and post a DIY for your loom wires and like with all my post, i take no liability. =)

Specs of Car:

R32 GT-R 1990

Nearly stock, no boost, full length exhaust and air pods.

Coil Pack cover off.

PROBLEM

For a little while now my r32 has been stuttering under full load. Key word is load, i will elaborate later. If I was to apply full load, ie. foot to the floor, the car would start to stutter (pop, hesistate, go like it was farting). I couldnt identify the problem at the start and had many other things looked at. Initially I thought it was the AWD/Attessa/transfer case, fortunately it wasnt as I had all these checked. I came to the conclusion it was to do with electrical in the engine bay. Spoke to many many ppl and the general consensus was Ignitor pack/coil packs/looms that connect these/spark plugs.

HYPOTHESIS

After further inspection I had removed the ignitor, ignition looms, coil packs, spark plugs, and found from these a very serious issue in the wire loom.

This is a photo of the culprets

post-16885-1211011513_thumb.jpg

The wires in the loom as you can see have created a hole in the insualtion wrapping provided at factory. You will not be able to see it but one of the wires has a crack in it, most probably allowing an arc of electricity to escape.

post-16885-1211011550_thumb.jpg

Here is a photo of my spark plugs, I have no idea how long they have been in there. As you might be able to see the 4th and 5th spark plug have suffered some damage to the tips. Im no plug expert, but at my guess it would be due to incorrect sparking or not sparking at all.

post-16885-1211011588_thumb.jpg

I believe that this crack in the wire is causing my dilemmas and will be fixing it very shortly and buying new plugs.

Well I hope ive given others some idea to similiar issues are in the same boat and can identify their problem.

Arb

post-16885-1211011569_thumb.jpg

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https://www.sau.com.au/forums/topic/219626-rb26-spotted-problem/
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good news mate, you can get a brand new loom from nissan for about $120 :D

Cool, thats price isnt that bad.

Are you operating your rb26 without the coil pack cover? I have this strange feeling that since i have taken off the cover, over a one year timeframe and the age of the loom, the plastic has been subjected to "irregular" heating and cooling cycles. What I mean is, when the coil cover is on, the heat built up in there allows for "regular" heating and cooling of the enclosed area. With it off, the plastic doesnt shrink or expand as it usually would, most likely at a faster rate, and at that age it is not used to the "irregular" rate of shrinkage or expansion because of the cool air allowing to flow over from the front of the car.

Otherwise it was just a sh*tty wire.

Lawl

my cars not a great example, it has spent the last 5 years as a race car. I replaced it because the loom was really brittle and I wasn't getting a great connection between the loom plug and the coilpack.

  • 1 month later...

Since my last post i have cancelled out a few things:

not fuel pump;

not ignitor pack;

not coil wire loom;

not coils;

not spark plugs;

not earthing cables;

not afm's;

not wheel rolling diameter.

Other things I have done, possibly not related:

changed gearbox oil;

change transfer case oil;

checked attessa resovior.

I am currently working on the fuel injectors as I found a bad seal that had fuel mixture around the seal [This seal is the one between the engine and injector]. What I saw when I removed the rail and injectors was that out of the 6 injector seals, 5 stayed on the engine and 1 came out with the seal, which that one had the residue on the seal. If that came out nice and easy, what could happen under cylinder combustion? going to clean the injectors and then replace new seals.

I want to have a look at the fuel regulator at the end of the fuel rail, but that will be after the injector clean and seal replacement.

Additionally another thought is, this "worn" seal is on cylinder 4 corresponding to spark plug 4 in the pictures above. When you look at the condition of the plug and from all the information i have gathered, there seems to be a link with the colour and condition of the spark plug with the worn seal.

hmm... more later this week.

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