joshuaho96

Sonax rubber protectant? That won't magically make those rubber seals look brand new but it'll help keep things from getting worse. It'll also make it look less faded for a while.

You have a point there, but the finer points of how the sensors work tends to be a reason why tuners don't like MAF-based tuning. The old hot wire sensors will see weird behavior in transients that requires min/max clamping. Card style hot film is better about reversion but the other issues still apply. There's also all the fun stuff that comes with MAFs on heavily modified intakes, usually OEM engineers sweat those details so there aren't weird issues causing a lot of noise in the MAF signal, etc... I've talked to a number of tuners and even Haltech USA tells me nobody seems to care about MAF support in their ECUs, so they don't really have a lot of experience there. Link support will also say similar things, their near-universal advice is run speed density on their ECUs because tuners don't really use the MAF support so they don't put much effort into maintaining it properly. Personally I don't care, if the factory setup is MAF and after thinking hard on the tradeoffs MAFs still make sense then I'll do whatever it takes to make it run properly, but I don't think that's how most tuners operate. Yes, there's no need to revert a Nistune mod. Personally I would keep it even after switching to a Link as a diagnostic tool while developing a base map properly.

The Nistune is a daughterboard that attaches to the OEM board. The Nistune Type 4 WC34 JECS board uses your OEM Consult port to connect to a tuner's laptop rather than cutting a hole in the ECU case for a USB port. So it is a fully reversible mod, especially when it comes to changing your ECU out for a Link standalone. There is no point in bothering to revert your ECU back to factory condition once you get a Nistune installed though, if you want the factory ECU map you can just flash it at any time and it will work just like factory. The only difference is unlike the OEM ECU you can see even more live diagnostic data. You will lose some conformal coating on the OEM ECU board in order to get to the solder joints so don't drop water on your ECU for any reason after that unless you apply new coating. Tuning Nistune requires a different approach to how you would tune something like a Link, both because you're dealing with what is effectively compiled code (how the ECU does the math) and because the ECU uses MAF primarily as the load scaler. Most people are unfamiliar with how MAFs work.

I forgot which section of the forum I'm in. If you have a WC34 S2 with a JECS ECU then it can be remapped with Nistune. Load index maxing out at 88 is an RB26 thing, not RB25.

If you have a Nistune you can read the TP load index, if you're hitting 88 that means you've reached the limits of the stock map. Maybe you have a very high RPM/load misfire that is going to get worse but it could also be that you need a slight remap.

If the car is overboosting it will hit an R&R corner of the map. The calibration engineers set up the map so that as you exceed the load expected by the stock turbo the engine will run noticeably rich and pull ignition timing. I believe there is also protection if you exceed the airflow the MAFs can read.

https://www.gtr.co.uk/threads/n1-oil-pump.565753/#post-5759331 The N1 pump has the same flow rate as an RB26 OEM pump, the difference is basically in the gear dimensions and profile.

AFAIK in the RB26 section of the service manual it explicitly says not to take apart the AAC valve. If you took it apart once there's no harm in taking it apart again to see if you can save it.

Your oil pump has to have some amount of backlash in the gears, otherwise any little bit of a thermal expansion would probably cause the gears to bind and destroy the entire assembly. When you have a rapid transition from acceleration to deceleration like a hard fuel cut I'm pretty sure that the oil pump gears and the collar on the crank are not staying in perfect contact with each other, instead they're changing RPMs at subtly different rates. So the steady state load you'd predict from something like a pull to 7000 RPM is no longer valid, instead you have to consider the maximum relative acceleration and the resulting impulse from impact when that lash is taken up again. Some sources: http://www.skylife4ever.com/2011/01/real-problem-with-rb26-oil-pump.html

If this is a two wire knock sensor you should verify that there isn't a short to ground. Also make sure you don't have a marginal connection by tapping the wires while you test their continuity. If you have solid contact with the terminals the whole time but you see resistance changing as you move the wires around it's possible that there's a break in the line that is just staying connected part of the time.

If you choose to retain the stock AAC valve and want to buy a new one the cheapest source I found in the US was PartsForNissans: https://www.partsfornissans.com/p-jdm-nissan-r34-skyline-rb25det-neo-idle-air-control-valve-b3781aa500

Doesn't it logically make some sense that the factory low mount manifolds are going to spool faster than high mount? To generate pressure on the intake side requires backpressure on the exhaust side, the more exhaust volume you have to fill the slower that happens.

You don't even need to search for previous topics that talk about all of these questions, this has already been answered in this thread. The -9 is barely different from a -7. They will bolt on the same. As for response and power you can either look at the compressor maps already posted and other comments in this thread or use some google and find threads like this: Tuning ICE is not exactly for the faint of heart and RB motors are especially expensive to make mistakes on. Don't be penny wise pound foolish about this stuff. Again, you should think deeply about what you want from the engine before you start putting down the better part of 10k USD to modify it. What do you like about the engine/car as it is now? What do you want to change about it? What is important to you? What do you want to use the car for? If you can't answer those questions clearly you shouldn't change anything until you can.

Instead of just guessing you should unplug the solenoid connector and measure the voltages on all the pins with the ignition on. If you see the ATTESA controller engaging the pump solenoid and the pump is locking up the transfer case then there's no point in trying to replace the pump assembly, it's just doing what it's being told to do. I would be concerned that you have something in your car's harness that is injecting voltage to the pump solenoid even though the ATTESA controller is not commanding it. That would definitely throw a fault code as the controller can detect what appears to be either a short circuit or open circuit.

Personally I would do flex fuel these days not only for all the performance benefits but also as a futureproofing measure. Even if oil extraction stops for the most part as cars electrify the US will almost certainly have tons of ethanol, especially as cellulosic ethanol starts reaching mass production. E85 in my area is already substantially cheaper than the 91 AKI E10 that passes for "premium gas".

It's a very simple circuit, chase the wires. Shouldn't be seeing any battery power to the solenoid with the car off, the positive side is shut off by the ignition switch.

The way to test for hinge bushing wear is to open the door, then try lifting the door. If there is non-trivial free play you're going to experience issues like this. Usually it's the driver side door that has this issue though.

And if you’re going to bother with wiring a pump and relay you may as well do PWM fuel pump control. I wouldn’t bother with trying to source a good R32 ECU with Nistune for an R33/R34 with no type 6 boards available.

I have recently sent my OEM RB26 injectors out for service as a part of preparation for California emissions. Also as a part of that because I really don't want to waste perfectly good o-rings 6 months down the road I asked them to test the dead time and all that fun stuff. The spec for the stock injectors at 3 bar was something like 480 cc/min, I got 500 cc/min on average. The OEM ECU reports 0.77 ms dead time, their testing reported closer 0.5 ms. I asked them multiple times whether that made any sense, especially whether 4 bar having roughly similar but slightly lower dead time was normal for old injectors. Their answer was yes. I haven't started engine map development yet so I can't say whether their report was truly accurate but something to think about.

Definitely don't parts cannon your way out of this. As a part of the cam belt service the CAS has to come off. I would look very carefully at the CAS and the bits that it interfaces with to verify that nothing is worn or has play. If for whatever reason it was binding against the cam drive that could cause the symptoms you're seeing. If you're worried about plugs pull them and inspect them. It's not a modern car where pulling plugs is a massive ordeal so it's fine to put used plugs back in if there's nothing wrong with them.

Just use car wash soap on a cold engine, don't use a pressure washer. Don't use anything crazy like Superclean which is sodium hydroxide.

Regarding this picture: The leftmost hose barb is for boost control. The "water tube assembly" you're talking about has both vacuum lines and coolant pipes. That is the green line pictured on the vacuum diagram labeled as the boost source. The second from the left is the air feed for the cold start air valve, Nissan calls it an intake air regulator. That's a valve with a bimetallic strip in it that closes as it heats up. This piece is right under the intake manifold and is basically impossible to get to without pulling everything else off first. The rightmost is the AAC valve air feed as you have mentioned. The factory system is super basic bleed-style, when the solenoid opens it is bleeding the green boost source line to the rear turbo pre-compressor inlet, the wastegate actuator sees less boost as a result and doesn't open as far. As for how you should set up your MAC (presumably 3 port) solenoid, I would reference this article which details it pretty well: https://www.onpointdyno.com/boost-control-plumbing-get-it-right-save-money/ My entire intake side of the engine is still in pieces scattered across the garage so I can easily take photos of all this crap if need be, including how the lines should be and what they should look like. Keep in mind there are special orientations for a lot of these hoses, the manual likes to make mention of this multiple times.

I've never understood why people do this when there is a dedicated fitting on the back of the balance tube for the factory boost gauge.

I would recommend the DW440 brushless over that pump, they have an S14/S15 install kit so it's direct fit for the R33/R34s as well. If you're going to run new wiring and all this other stuff you may as well spend a little more on the pump and have something truly E85-proof. The brushed fuel pumps that are E85 compatible will still have a shorter lifespan on E85, brushless fuel pumps don't care at all. I am big on buy once cry once though.

8.5L is the system capacity, how close you will get to draining all of it depends on how far you go in draining the car. Coolant choice depends on what coolant you already have. If you have the Nissan green or blue then use that. If you have something else in the system then get the same. If you don't know what you have and don't want to take chances then flush the system with distilled water, then refill with whatever you want.