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R32 GTR RB26DETT


Jjtxaz24
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Right back to the start of the thread, I think you've just got a boost leak.

Check all the big hose clamps between the airbox and the plenum including under the front bar, and also the medium sized stuff in the BOV fittings and their return line. Also check the BOV return (plastic) for big cracks.  Potentially but less likely, you may have other smaller vacuum line problems

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13 minutes ago, Duncan said:

Big red arrow to square box is the factory MAP sensor, just runs the factory boost gauge. Small red arrow thing on the right is aftermarket but probably for aftermarket boost control.

yes, green arrow should plug into back of manifold balance pipe, if it was off that is a problem. It is a crappy hose on a crappy fitting with no lip so it is easy to blow it off under boost, small cable tie can help

Ok, well that helps. Thank you.

When I plugged that hose to the manifold balance pipe it quite down the clicking but it was still there and still misfiring. I'll clean that nipple off and slide that back on and zip tie it. 

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13 minutes ago, Duncan said:

Right back to the start of the thread, I think you've just got a boost leak.

Check all the big hose clamps between the airbox and the plenum including under the front bar, and also the medium sized stuff in the BOV fittings and their return line. Also check the BOV return (plastic) for big cracks.  Potentially but less likely, you may have other smaller vacuum line problems

I've got an aftermarket BOV in there. I'm sure the small plastic piece that runs behind the intercooler I blocked it off and removed the stock twin BOV. 

I'll check the clamps to make sure they're all seated. 

I appreciate the help. I'm really at a loss and this gives me some direction. 

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1 hour ago, Jjtxaz24 said:

I've got an aftermarket BOV in there

Externally venting? You know we're going to point to that as a significant risk to the satisfactory running of your engine. The factory ECU can only handle so much shit done against it.

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9 minutes ago, GTSBoy said:

Externally venting? You know we're going to point to that as a significant risk to the satisfactory running of your engine. The factory ECU can only handle so much shit done against it.

Yeah it's an HKS BOV. It doesn't get recirculated. The engine is pretty much stock other than some tomei pon cams. I installed em about 1k miles ago and hadnt had any issues with the car aside from some early on (last year) bad coil, ignitor and wiring harness and overheating (bad thermostat and fan clutch and radiator) lot of maintenance has been done to get it as a good DD. 

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I was able to source/borrow some splitfire coilpacks and stock injectors that I'll use tomorrow to see if my set up is garbage and toast. 

If my friends known working Injectors and coils still produce the same issue then I guess we chase down vacuum leaks. After that I might just LS swap it and be done with it. Lol. 

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Alright update time. 

Installed the split fire coils and fired it up - same issue.

Installed his injectors and left the spitfires installed - same issue.

I took off coils and took out plugs and took a look inside the cylinders: inCollage_20200504_172538227.thumb.jpg.769c07b6ef719737f1e5d5c7027ae0ec.jpg

That's what it looked like inside the cylinders. 

The plug in 6 was black again, I read I could gap em at 1.1 (oem gap size) when I put em in new so I did that and it drove fine. I brought em in closer to .8 just now and fired it up. Same issue - The plugs I'm running are BCPR7EIX. 

I downloaded a vacuum diagram for the RB and traced my lines. They are still on and none are lose. I used some soapy water and sprayed down the rubber lines and no bubbles. I don't have a compressor though so I cant pressurize the system. 

Here's another a video as it sits with the troubleshooting listed above: when I unplug cylinder 6 coil ticking stops, if the vacuum line is not hooked up to the balance pipe it's a lot louder. All plugged up its fairly quite but still misfiring. 

here's my boost gauge and wideband at idle: 

 

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The only sure way to eliminate boost leaks is by pressurizing the system . You can't tell if a joint is leaking just by looking at it and often boost leaks occur out of sight.

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Yes, yes it does. I've had 2 failed engines in the past from losing the spark plug ground electrode and it did exactly this.

Ever lost one of the plug tips in the past ?

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9 minutes ago, BK said:

Yes, yes it does. I've had 2 failed engines in the past from losing the spark plug ground electrode and it did exactly this.

Ever lost one of the plug tips in the past ?

The last plug I changed on cylinder 6 was still in tact, since owning the car I've never had this issue till now and when i pull that plug (about 2 weeks ago) and this one one now they were still in tact just really black. 

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24 minutes ago, KiwiRS4T said:

The only sure way to eliminate boost leaks is by pressurizing the system . You can't tell if a joint is leaking just by looking at it and often boost leaks occur out of sight.

Ok so I'll have to get a hold of a compressor and try to do that boost leak test. 

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9 minutes ago, GTSBoy said:

The question will be, if the current plug tip is black, why is the piston crown carrying fresh, shiny witness marks?

That is a very good question. I got a little close with the camera trying to gauge the distance I was at. Not enough or hard enough to remove any carbon or anything though.

So if the plugs have just been fouled, not missing any pieces. 

This problem is driving me insane. I still gotta rule out the boost/vacuum/pressure leak. 

I really dont wanna pull the intake and turbos off to get the head off. I'm moving in a few months so if it's an extensive fix it's just gonna sit on the back burner till I relocate and get settled in the new house. 

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1 minute ago, GTSBoy said:

Ok, so.....ponder how the gudgeon pin might be f**ked, or something else that permits the piston to jump up further than it is supposed to and contact the plug (and simultaneously make a noise!)....etc.

Guess the only way to figure out is to pull the engine out and tear it down. Not something I wanted to do but most of all troubleshooting has been exhausted on my end and it keeps pointing to pulling the engine. 

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27 minutes ago, Jjtxaz24 said:

Guess the only way to figure out is to pull the engine out and tear it down. Not something I wanted to do but most of all troubleshooting has been exhausted on my end and it keeps pointing to pulling the engine. 

If there is a straight line from the plughole to the piston you can try this: Remove the plug and put something in the hole that will stick out of the top. Turn the engine over by hand until you observe tdc and then see the piston  starting to go down again. Then use a strong (probably wooden) stick and try to push the piston down. If it moves appreciably without the engine turning you have a problem.

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2 minutes ago, KiwiRS4T said:

If there is a straight line from the plughole to the piston you can try this: Remove the plug and put something in the hole that will stick out of the top. Turn the engine over by hand until you observe tdc and then see the piston  starting to go down again. Then use a strong (probably wooden) stick and try to push the piston down. If it moves appreciably without the engine turning you have a problem.

I  can try that. It takes me like 5 minutes to take off all coils, wiring harness and plugs. 

I'll  need to take the fan off and out the way to have access to the crank bolt and I can turn it over by hand and see if that works. I'm assuming (brains not working anymore) I need to jack up the car on all 4 corners? Havent done that yet. 

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57 minutes ago, Jjtxaz24 said:

I  can try that. It takes me like 5 minutes to take off all coils, wiring harness and plugs. 

I'll  need to take the fan off and out the way to have access to the crank bolt and I can turn it over by hand and see if that works. I'm assuming (brains not working anymore) I need to jack up the car on all 4 corners? Havent done that yet. 

No. Just need to put it in neutral. If you put a wire on the starter solenoid you may (or may not) be able to inch the motor around.  If you take all the plugs out you may (or may not) be able to turn the engine by the fanbelt if you can hold it on the fan. Otherwise yes, spanner.

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6 minutes ago, KiwiRS4T said:

No. Just need to put it in neutral. If you put a wire on the starter solenoid you may (or may not) be able to inch the motor around.  If you take all the plugs out you may (or may not) be able to turn the engine by the fanbelt if you can hold it on the fan. Otherwise yes, spanner.

Alright, I'll give it a try tomorrow. 

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