joshuaho96

As far as I know there's actually a yaw sensor in the back of the R33 and R34 GTR which is used for HICAS. It vaguely helps maybe. In practice the R33 and R34 group N cars AFAIK kept the yaw sensor but deleted the HICAS and fed the signal into the ATTESA/ABS controller instead to control the A-LSD.

I have had two separate R32 owners tell me about 2-3 incidents where they were either in a turn and the HICAS was trying to make the car go straight or they were going straight and the rear end was crabbing out to try and make the car turn. Neither could get it to reproduce again afterwards. It absolutely destroys confidence in a car when the system can randomly misbehave like that. My R33 doesn't do that but I have heard of bad yaw sensors causing behavior like the rear end crabbing out under braking or excessive vibration/exhaust noise doing something similar as well. The R32 doesn't have any form of feedback control and as far as I can tell the HICAS is really far more aggressive compared to the R33.

Almost every I know with an R32 GTR has some story about the HICAS trying to steer them in an unintended direction. The R33s seem more reliable in that regard. I'm pretty sure my HICAS is not locked out and I can't even really tell if it's working or not.

I can get it to idle at 800 rpm if I wanted to, but the engine feels rough and genuinely unhappy to be there if you put any load at all on it. Not like my LS400 which will happily idle at 400 RPM if you put it in drive.

Idle target on the emissions sticker says 950 rpm with 20 degrees of timing. I probably need a new harmonic balancer but I get nasty vibrations much below 800 rpm. I'm pretty sure the AAC also contributes to cold start airflow looking at the Consult logs, it just needs the extra help courtesy of the cold start valve. I'm probably not explaining it too well but the cold start idle target at 20C coolant temp is something like 1400 RPM, then if you start slipping the clutch and don't give it any throttle to compensate for the drop in RPM the ECU reacts by really opening up the AAC valve and keeping it there. Pressing the clutch pedal in it's not unusual in my experience to see it hit 1800 RPM until I wiggle the shifter in neutral enough for the neutral switch to work and the ECU to slowly drop the idle back down. Anti stall in hindsight was definitely the wrong word for it, that's more like a clutch position sensor that will raise the idle proactively instead of reactively. It's more like the idle control is very willing to try and catch a falling idle and is not that quick to deal with a high idle. I have dreams of finishing a Haltech base map eventually. No tuner is going to bother with my weird obsessions so I'm going to have to DIY all of this.

I run factory ride height + suspension. The car already barely fits the floor jack under it and my local roads are not good enough to lower it any more. It's not aesthetically pleasing but that's life.

OBD2 always has battery voltage present on some of the pins. I'm willing to bet someone shorted something or damaged it.

I'm pretty confident I have the stock clutch in my R33. It is far and away the most forgiving clutch I've ever driven. The aggressive anti-stall + factory 950 rpm idle also makes it hilariously easy to get going even without throttle application in first. The slip zone feels a mile wide. The vacuum assisted clutch master also makes it feel lighter than something like an S2000. The factory idle control is probably not intended to be anti-stall or anything like that but it reacts to persistent low idle by ratcheting up the AAC duty cycle to max which gets you to like 1400-1500 rpm and even higher when the engine is cold and the cold start valve is still open.

NZEFI is in NZ, so it's 705 NZD.

Keep in mind the factory rail is 10.5mm, you need adapters like this: https://www.efisolutions.com.au/bosch-980cc-1100cc-fuel-injector-kit-x6-rb26-gtr-r or this: https://www.nzefi.com/product/nissan-rb-1000ccmin-top-feed-direct-fit-fuel-injector-kit/

Don't buy those DW 1000cc injectors, they look like EV1s. Get the Bosch 040 980cc injectors instead, EV14s are readily available and dramatically better. You do not need an aftermarket fuel rail for the kind of power you're talking about, but if you intend on running a 400 lph pump at full speed without using something to slow it down then you will need a big FPR like the Aeromotive you listed. If you're doing the timing belt you should always do the water pump as well. Those two go together. Not as mandatory as it is on a BMW or Porsche where the pump will explode the second you get past 75k miles but you still don't want to play the odds.

0.6 to 0.7 bar is still low if you've bypassed the solenoid and you're venting the wastegate vacuum line to atmosphere. Have you checked how much exhaust backpressure you have?

The R33/R34 lost the valve on the heater core due to cost cutting. Their grand solution to this problem is to simply keep airflow from going through the heater core with the blend door. One thing I've noticed is that the cabin on the R33 feels like it warms up more than it should and I suspect the lack of a valve to keep the heater core from warming up the dash is probably part of it.

At least on the R33 GTR it seems to me that the factory cat EGT sensor is towards the back of the car, you can see the wire sticking out of this one:

Unless you're putting a wet clutch DCT or a ZF6HP or ZF8HP manual is the way to go. Automatics that don't have the lockup clutch running in all forward gears and modern shift logic are just really frustrating on something nominally meant to be high performance.

Basically yes, if you disconnect the FPCM and ground pin 4 and 6 on the connector you have bypassed the factory FPCM. If the pump gets power from the fuel pump relay it will run full power immediately. You can see the same idea discussed for Z32s here: https://conceptzperformance.com/wiki/index.php/FPCU_Bypass_(2-Seater) If the pump isn't running then it's safe to say that something is wrong with the ECU. Initial key-on should cause it to beep as Duncan mentioned. Then it will shut off after an initial prime. I would also verify that this isn't a NATS issue or something.

Open up the ECU. Verify that nothing is burned, no caps have dumped their dielectric or burst. To eliminate the FPCM to narrow down the ECU as the fault you can bridge pins 4 and 6 on the FPCM connector directly to ground. If bypassing the FPCM like this does not change the behavior then you know the ECU has failed. As for how someone could have damaged the ECU this way I don't really know. It is possible someone grounded something improperly and is putting way, way too much current through the ECU ground planes which can cause things to break. Not all ground points are equal, see this explainer to get an idea for what I'm talking about: https://www.haltech.com/news-events/ecu-grounding-the-dos-and-donts/

For the RB26 ITB + turbo causes a lot of weird issues I think. Most of them are just ITB problems. At idle or low load IMAP is a very noisy signal because there's not that much vacuum volume. You can sidestep this with aggressive filtering or sampling based on crank angle but that makes it a slow signal. Then once you start using the throttle while I can clearly see vacuum during some part throttle cruise cases it easily saturates to atmospheric and spends a lot of time sitting around there for a solid half or more of the throttle travel until it spools the turbo. During cold start you also have to account for the fairly scattershot behavior of the cold start valve. The ECU doesn't even know of it's existence and it operates off of a very eyebrow-raising method of heating a bimetallic strip as soon as the fuel pump gets power to slowly close the shutter. It can get stuck open or start closing at a different rate with age so its relationship with actual engine warmup is loose to say the least. Then of course wastegate duty and all of that fun stuff affecting EPR also needs to be compensated for. My car has 4 cats on it from CA's emissions compliance requirements which has made a very, very noticeable effect on how much cylinder filling occurs despite running wastegate boost in both cases on an otherwise similar car. It used to hit the R&R corner of the map, now it actually doesn't exceed the factory intended load scale. I don't want to bother with tuning an engine twice in response to something as simple as a different exhaust. I've never tried EPR-based load to see what happens there but maybe in the future I might be able to muster the effort to evaluate it against the MAF load data to see if it helps tame the non-linearity problems. For now I plan on just using the factory MAFs and building a MAF load tune, then going from there. It's coming along well but the final 15% to make it drive like a factory car is taking 85% of the effort.

You can try tapping the MAF or tugging on the plug while the car is stopped and see if it reproduces. Not unusual for MAFs to have failed solder joints when old.

Looks like you want to check for power and ground on the CAS, then try seeing if there's continuity on the cam/home and crank signal wires from the CAS to the ECU harness. You can try also backprobing the ECU connector to see what kind of voltage those wires are delivering in the specified conditions in that table. Easiest way of course is an oscilloscope to read signal from those pins but not sure you can easily find one of those. You can also just use NDS while cranking to see if it reports RPM. If it does the ECU is getting some kind of signal. Oscilloscope will tell you how noisy it is.

What is the actual code? These aren't OBD2 cars, they don't use OBD2 generic codes. If the starter is dead it won't crank. Most likely the code is that your ECU is losing the signal from the CAS altogether for whatever reason. The ECUs in these cars are pretty basic and don't do anything like cam correlation codes or any other plausibility checks.

You need to do the following diagnostic flows to narrow down the issue: If you need a wiring diagram you can find it here under A-LSD/ABS: http://yariksteel.ru/manual/R33/Skyline_R33_elektroprovodka.pdf

I think he ran into similar issues, once it actually kicks over he experiences lean running for a little bit before it corrects. I suggested just papering over that problem with after start enrichment at high coolant temps but the whole thing is getting redone with a crank sensor because he's sick of fighting the distributor which was constantly misfiring at idle but weirdly not at cruise or full throttle. I'd see something like a full point of AFR lean-out in response to a misfire so I disabled all closed loop corrections even after I was done messing with VE tables. He's also using one of those old style AEM controllers that blasts the heater the second it gets power from the ignition switch so the sensors aren't going to last very long regardless and there's no real failure detection in those controllers either to my knowledge. Once he gets the new setup running I'm sure I'll have new and exciting issues to learn about.

Supposedly yes, but I have a theory that both are suspect. Haven't been able to get a pressure gauge on it to monitor what it's doing after shutdown as I got busy with other things since then but I suspect it would be interesting. This is a series 3 Jaguar E-type convertible. Prior to this it had Stromberg constant depression carbs which were absolutely horrific between that and the bizarre early 70s emissions vacuum retard distributor. I definitely agree that the conversion nature makes it hard to actually disambiguate what's going on but at the time of the hot soak we had come back from a fresh fill so the tank was full. The whole fuel system was just redone for the EFI conversion so I would be kind of surprised if it's leaking inside the tank but anything is possible. At the time of the tuning session it still ran the factory distributor, actually the ECU didn't have any engine position so there's no concept of anything like fuel injection timing or ignition sync. Verified the spark plugs were in fact firing too.

Curious to know if anyone else has run into this issue before. I helped a friend tune an EFI conversion a little recently and an issue we ran into is that after getting coolant temp into the 90C range, after shutting the engine down and letting the whole engine bake for 5 minutes it wouldn't crank over anymore. Adjusting the cranking fuel pulse width did nothing. Surprisingly what solved it is setting a long fuel pump prime. He's running an MS2 or something like that so it wouldn't allow him to prime for longer than 3 seconds but keying on and off three times to get about 9 seconds of priming has reliably allowed it to restart now in this hot soak scenario. Anyone know a good explanation for exactly what's happening here? My working theory is that the fuel in the rail has boiled from heat soak and the pump needs to cool off the rail to have functional fuel injection again but I'm curious to know what others think.