R32 Nismo GTR engine

[andy66]

Hey looking for some input on what might be wrong. Drove from Kelowna to Penticton today and back ( drove it hard in places ) had no issues until i was almost home. Drove up to a light everything was all good before getting there. Sat at the light waiting for it to change, light changed drove away and this is where the issue started. Car had a totally different sound to it. Hard to describe, almost like a Subaru with an a/m exhaust on it. I didn't even think about boosting the car once it started making this sound. Luckily I was really close to come. No idea where to even begin diagnosing this. I'll post up a video of it because I really don't know how to describe it.

[clone]

Nice engine....
Have you checked all your vacuum hoses, for brittle or cracked. I had one that was ripped I replaced it with canadian tire wiper hose.
it was located near the driverside firewall.

[MarusGTR]

You could have a dead cylinder. Does the engine shake a whole lot, like the crank is unbalanced?

Follow the standard troubleshooting procedure by ruling out common denominators of missfires, if you haven't already.

-Check coil plug resistance. 0.6-0.9ohm target.
-Check your spark plugs' electrodes. You could of blown one. It happens.
-Check injectors by unplugging one at a time while the engine is running. If there's no change in tone or sound, you could have found a cylinder with an underlining problem.

It could be vaccum or accessory based, but I recall RBs with dead cylinders sounding like boxers. Mine did when I forgot to plug back an injector once. Keep us updated.

[evilgtr]

I blew a intercooler hose off and it sounded lime a wrx, start with the simple stuff first. Pressure test charge system and vacuum system

[andy66]

Motor doesn't shake at all. It sounds like it's coming from the exhaust side of the engine by the rear turbo. The exhaust sounds like its misfiring at but idle but i've never heard a car sound like this just from a miss fire. I'll check my plugs, coils, injectors and intercooler pipes tomorrow morning and see if i can't find something there. I'll get a better video of the problem tomorrow morning (the one I took sucks) as well if none of the above solves it.

[Bruizer]

Ignition system if it sounds like a Subaru. Plugs or coil packs usually.

[MarusGTR]

I blew a intercooler hose off and it sounded lime a wrx, start with the simple stuff first. Pressure test charge system and vacuum system

That'd make sense, since would happen all of the sudden. How does one check the charge and vacuum system btw? (just wondering)

[Gordoskin]

I didnt fully plug in my ignitor box at back of the coil cover and it sounded like a subaru, once i double checked the connection it was all good

[andy66]

Check all the plugs they looked like this



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put them all back in started the car up sounded fine, let it warm up fully. Took it for a drive, it ran fine. Boosted fine, hit full boost no problems. Parked it back at the house let it sit there for maybe an hour, took it back out on the road all was good. Got to a light, gave it a little rev up to to 2000 rpm and it started making that sound again. Drove down the road some more it was stuttering while cruising but if i boost it the stutter would disappear. Came to a stop at a light still stuttering, misfiring, whatever want to call it. Light changed took off boosted through first, shifted into second, got a fireball out the tail pipe,boosted in second up to the speed limit shifted into third and got another fireball out the back. After boosting it a little the stutter/misfire was gone and it drove perfectly fine again. Parked it let it sit at my buddy's house came back to it maybe 2 hours later and drove it home without any problems. So i know the plugs are fine next step check the coils maybe ? Anyone care to give me a quick run through on how to check the voltage on them ? Any other idea of what it could be ? Besides all of the above that's been mentioned ?

[DarkCaporaL]

Yeah sounds like coils are failing. Take a visual look at them and see if there are any cracks.

You can test the resistance on the coils if you want, but to be honest, testing it is pretty pointless, it will only tell you if they are completely toast which is pretty obvious when one is. A slow failing one will often read the same resistance as the others.

Anyhows, if you take them out, you test the resistance between the + and - on the connector. If the resistance looks normal, something like 0.5 (I forgot the exact number) then it's ok. If it's 35682349586234578 then it's not. Most likely all your coils will all be at the same resistance.

Make sure to clean your plugs and check the gap to 0.08 while you're at it.

[Skym]

Sounds like airleak behind MAF. If hose clamp on MAF is loose or there's hole in the rubber piping, AFM gets 2x air sources and engine starts stuttering (similar symptoms to coilpacks failing, so can be mistaken for failing coilpacks). It happened to me when exiting motorway and then applying throttle would make it go away (same with coilpacks when they failed). Talked to Nissan Dealership and they confirmed the AFM leak, 2x air source problem, so seems to be common.

[andy66]

I'm going to cave in and spring for a set of coils. Might as well do it anyways seeing as i'm still running the OEM ones. Hopefully this solves the problem. Took the car out today for and its stuttering through the whole power band, now boosting or not and running really rich. It smells really rich and you can smell it pretty easily. So i'm guessing that means one of the cylinders isn't firing and just dumping the fuel through the exhaust , making an awesome fireball out the back ?

[DarkCaporaL]

When it studders, unplug the coils one by one to find out which one isn't firing. The one where you see/hear no difference is the cylinder that's not firing. Then you can try switching the coil over to another cylinder to see if the problem follows it.

I would also do an airleak test like Skym suggested, it doesn't take too long. Easiest way is to remove your intakes and block them off, then pressurize the system through any vaccum line.

If you're buying coils check for the Yellowjacket group buy going on, they're cheap and fantastic.

[derbeck]

i would try a maf resolder nothing to loose

[andy66]

Fixed the issue it was the coil on cylinder 4 and my coil wires were brittle. The plastic inside the clip ended up breaking haha.