GTSBoy

Ever wondered why your air-con doesn't work? And no, you cannot service your tailshaft yourself. Take it to a mechanic, or a drive specialist like Hardie-Spicer.

You got the R32 (ECU) wiring diagram? It's in the R32 GTR manual.

Yes, well, I don't know about the studs (in my application they would reasonably be considered overkill) but I may try some copper nuts.

Yes, absolutely. At least when it is actively controlling boost. I think if the gap is wide enough to leak noticeably during spool, that it will kill spool (compared to having the WG held closed by the controller, like it is supposed to be). And after tightening it back up and having it feel a little better coming on boost, it was probably leaking enough. Most of the time yes. I don't have anywhere near as much power as many on here have, but even that is enough to cost a great deal in tyres and -ve attention from the guys who drive the unmarked cop cars.

Had a little fun on the weekend, thought it might be a learning moment for some others. Recently there have been odd squeally noises when my car was on boost. Not all the time, usually while not fully hot under the bonnet. Intermittent nature of it made me wonder if it could be a gasket leak on the hot side (sounded like it was on the LHS of vehicle). Sort of gradually became a little more frequent. So I chucked the inspection camera in under the turbo heat shield and found, to my mild horror, that the rear lower turbo nut had dropped off at some point. The lock tab for it was still bent up sufficiently that you'd think it impossible for it to happen. But happen it did. What was somewhat more frightening was that peaking the camera on the other side showed that BOTH the other two nuts on the front side were loose. Several threads out. Both still in contact with their locking tabs. WTF! Only the top rear nut was tight. So there you have it. Turbo was barely held on to the manifold and I could barely tell the difference in the car's performance. Sure, it was no doubt a creeping death onset and I didn't notice the slow decline in its spooling response, but it was still pretty much as fast as it ever was. After doing up the one nut that I could actually get a tool onto (so obviously, I have some more work to do!) it doesn't shriek any more and it seems to come on boost a little more aggressively. But there you go. It is surprising how little effect having the turbo almost to the point of falling off can have.

If you chase the wire back from the compressor and its relay, via the refrigerant pressure switch, it goes down through the small engine loom connector M and on to ECU pins 40 & 9 (which are marked as being RB20 specific). Which engine did this car originally have? RB20E, or RB25DE? The power that runs the compressor comes out of the 2nd 10A IGN fuse in the box. Runs out and down to the cabin temp sensor & up to power both the relay and the compressor directly. So the switched side of the compressor has to be switched somewhere.The only other wire on the relay goes over to the pressure switches, as I said in my first paragraph. So the ECU has to be responsible. and the ECU needs to receive a signal from the AC controller, and that really looks like the wire I was talking about in my first post. I can't see how it would work otherwise. I can't even see how they would be able to make it so that there might be a different (simpler) control unit for the cheaper car (say, the RB20 one, which might not have climate control**) and the full climate cars. They all look to be mostly the same on that diagram. ** I think R32s and the S chassis cars were like that.

Alright....looking at the 2nd of those images, I see that ECU pin 36 (and apparently ECU pin 31) are connected to the FICD solenoid valve. That's the Fast Idle (Control Valve, I guess). Used for idle up. So when the Air-con sends a signal out on that same connection, the idle speed will increase. Easy enough. What I can't easily read from the AC controller end of that grey wire is which pin it is connected to. But it's definitely not pin 27, because I see pin 27 on the far right hand side of the AC controller (4th image) and it is involved with the mode door actuator, or one of the other doors. If I had to pick a pin for that grey wire to go to on the AC controller, it would be 21, 22, 29 or 30. Beyond that it is starting to get difficult. If you look on the top of the first image yo will see 4 * notes describing which engine the various * notes scattered around the diagram refer to. Look next to the ECU plug and you will see 1 referring to RB20E, one referring to RB25 (and I think that solves the issue of pin 36 and 31 both being connected together - they probably aren't in the real world, only on a drawing that serves 2 different engine/ECU combos). So I think you need to consider what engine you originally had and what you changed to, where the old and new wiring looms are now and whether the power supplies from the fuse box (visible in the middle of image 1) are all connected where they should. By that last, I mean at least one power wire comes from that fusebox down to things like the cabin air temp sensor and on through connector A into the ECU (on the P wire HB05)

lol

See my answer in your other thread.

R34 NA RB25s have a separate TCU in the car for the auto. On the turbos, the TCU is a board inside the ECU. The only real question is whether the turbo manual ECU will talk nice on the system bus to the TCU. I would expect that it probably would not. The reason is that the turbo auto ECU talks to the TCU internally (whispering in its own ear). The turbo manual ECU does not expect to have to talk to any TCU, so probably doesn't send or receive ANY auto trans related messages. That might leave your auto's TCU struggling to work out what's going on. I predict bad things because of that. And it's not as if you can get an auto image dropped into a Nistuned manual ECU either. You can, there's nothing stopping you, but I would not expect it to talk to the external TCU, because it would be just talking inside the ECU - whispering in an ear with an earplug in it (or an ear that looks a lot like Van Gogh's.) The reverse situation is easy. I have an auto R34 ECU (with TCU inside) running the engine with a manual gearbox. That works because I am the TCU.

The turbo's limit is ~14 psi (subject of course to the truth that these are statistics and some die at stock boost!). The ECU has a strategy called R&R, Rich & Retard. It is basically just the high rev-high load part of the fuel and spark maps have massive fueling and very retarded timing, as a self protection mechanism. Makes the engine hard to grenade. It actually makes the car hugely slow, the more boost you add. About the max boost you can usually give an R33 ECU is about 10 psi. Maybe 11. Usually starting to get ridiculously rich by then though, and all you do is use more fuel to go no faster, if not slower. RB20s, by contrast, will more happily run up to about 14 psi on both the turbo and ECU. The ECU has R&R type stuff going on, but it doesn't act as early as the R33. On my R34 ECU I have had to tune out a lot of fuel and add a lot of timing just to get it to run ~12 psi (which is the hardest I am willing to run the turbo - it probably could take a bit more though). As to your boost controller. It doesn't matter what controller make/model really. They all use the same basic functions. Look up the guide for a Profec, for example, and see what the advice is. It doesn't matter what the actual values of the numbers are. Just what the changes to those numbers cause. Turn the gain up and the boost should go up. There's usually one of the settings will set a point below which the controller will try to keep the wastegate shut, to help speed up spool. Increase that and it will come on harder, but might spike into overboost. So you set the gain, then fiddle with the ramp setting. Then you look to see if it is losing boost at high revs or if it is not controlling properly (is boost is rising above your gain setting) and use the third control variable to increase or decrease that behaviour. If it's dropping boost up high, you generally increase the third setting. And vice versa. Just fiddle with it and you'll see.

What are you doing for management? You can't run 13 psi on a stock RB25DET ECU. It will tell you to go stuff yourself and give the engine all the fuel and none of the timing.

Made a leak somewhere else? Could try the spray and pray with some carby cleaner. See if you can affect the idle.

A clamp meter is the smart choice there.

That's not a problem. Stag ECU will ignore the TCS motor and position sensor (if it's even there). I have Stagea image in My R34 ECU as part of the "kill TCS" you need to do when transplanting these things.

This is going to end in fault codes even if he can make the ECU pinout changes. Needs the DET boost sensor wired up for a start.

Is it a Neo ECU or vanilla? DE engine loom, or DET engine loom? Not that I expect you would have a good time getting it running on a vanilla ECU.....but there are things you need connected on the Neo ECU that you might not have taken care of. You will probably have to completely dismantle the IACV to clean it properly. They do get really gummed up.

Yuh - but needed the cubes.

Maybe post up some nice big screenshots of the diagram. I can look at R32 & R34 stuff at home, but it won't necessarily match, colour for colour, pin for pin.

Um.....the Air-Con controller tells the ECU that the AC is on and the ECU does some of the work. Pin 36 is pretty explicitly therefore the signal from the controller to the ECU. Doesn't matter that the ECU doesn't have anything else on that pint. In fact, the ECU does want anything else on that pin. I don't have any R33 wiring diagrams myself, so I can't look it up for you. But if you have them, then you have what you need to fix this.

Yuh....but is all of that still in it?

I'm with them. ^^^. Unlikely to be weeping oil from the head/block interface. Much more likely to be coming from somewhere above that. Clean and inspect after some more driving.

How would we know? How many miles has it done at this power level? How hard has it been run? What are the compressions? etc?

Possibly too small for E85 at that power level though. OK for 98, but would probably want to go to 1200cc for E85.

Use a good spray pack wheel cleaner. Non-acid very important. Will also need to scrub with scourer pads or similar. Should at least keep them waxed every wash, to keep brake dust etc off. There are other protectant thingos you can buy to put on wheels to keep the environment at bay, although I think the ceramic coat things go on painted surfaces only, not alloy.