Traah221

Anyone thought about how the one doing the test could be straight up doing it wrong? Sounds stupid, I know, but hey, it happens. If he keeps cranking it until the gauge needle stops moving, it would read around the 200 - 210 mark. Some people just plain don't know how to properly do a compression test. To OP, yes, 200+ is way, way too high. Look for a number around the 150-170 mark. Source: Cranking my RB25DET comp gauge pressure up to 205 across the board to perform an (admittedly ghetto) homemade leakdown test just by bumping it until the needle stopped.

Find anything interesting Matt? Update, haven't yet pulled the turbo to look at it, but did a compression test and still 155-160 across all cylinders. Since I didn't have access to a leakdown tester, I cranked the measured piston PSIs to 200 and let them all sit for a few minutes, looking for any change in pressure and/or audible leak from behind the intake, from the rocker covers, or from the exhaust. Nothing, all 6 held 200+ PSI for 5 minutes each with no hissing. Starting to think it's indeed the turbo, since I had a little bit of lateral shaft play.

Alright, so backstory on this issue is as follows. Series 1 RB25DET, was running pretty solid except for my O2 sensor was going out, caused it to run rough as hell until it warmed up. Installed an HKS GT2530, but the water lines off the stock block wouldn't fit so I had to delete them at the block, so the turbo is running oil only, no water. Still running a stock Rb25DET ECU and MAF. I took it for an easy test drive and all was fine, it should be noted that I took my O2 sensor out and soaked it in petrol, then used a heat gun to blast it off, which seemed to help. No more rough running when cold, but the misfires and shudders come back when it's warmed up now. Once everything got hot though, I noticed some blue/white smoke puff out of my exhaust after I took off from a stop sign. I watched it the whole time while driving normally and shifting, no smoke. It wasn't until I let off the throttle and let the car engine brake, and then gave it some throttle again that I saw another puff of smoke. So, it only burns oil when there is no throttle being applied, and the engine is decelerating. I popped the hood, and noticed one thing straight off, my PCV hose from the intake side rocker cover to the plenum was kinked, so I replaced that with a factory new one. Not much change, but should I tear down my whole PCV setup and make sure it's working properly? So, what would suddenly be causing this issue? I find it fishy that it started immediately after the new turbo was installed, but I also mucked with the O2 sensor and somehow the PCV at the same time. I have a Z32 MAF and PowerFC that haven't been installed yet, but would those possibly fix the issue? Or am I looking at something deeper in the head, like valve seals or something? Thanks in advance!

For some added comfort, I've traced a few RB20 harnesses for my RB25 conversion, and on every one the 2 green plugs are relays, easy, and the long white plug in your picture has never had a home, and the car has never had any problems running. Should be noted that all the in cabin amenities work just fine too.

Hm, could be a difference in a NEO swap to my S1 swap, but all I know is my cluster and windows didn't work without a 75A Main. Was that the resistance your Fuse had? If so, I'd say it's good, yes.

Hey, I hit this problem in my RB25 conversion, buck gets ten you don't have brake lights or turn signals either. Its your main 75 amp fuse. Even if you didnt need one before, after the swap you do. All your accessories run off the 75 amp main. Try bridging it with some wire and see if your accessories come on.

Hey guys, so I got managed to snag a GTR Frontmount for cheap at Upgarage here, and I couldn't find the actual kit to buy, so I got a universal 3" kit from CXRacing with lots of spare parts, straights, 45s and 90s, silicone couplings and clamps. I'm confident in making the piping fit myself, just some extra cutting and bending, that's no biggy. Thing is, it came with a new BOV I'd like to install, and it came with a mounting pipe for the BOV, so here's my question. Is there any way to delete the stock cross-pipe that hooks to my Throttle body that the stock BOV sits on? It has about 4 major vacuum lines running to it, could I delete some of them and just tie others into existing lines? Or am I going to be stuck drilling out some holes in place of my stock BOV to fit my new one on? Thanks for the input!

Haha, I agree completely gotRICE. Electrical gremlins, especially in a wiring job done yourself in your room through a series of wiring diagrams is just a nightmare.

Well, the IACV is meant to control your airflow at Idle, meaning if you turn on things that put load on your engine at idle (i.e. AC), it's going to change your idle speed to match. But for your issue, a good cleaning on the Idle Control Screw on your IACV will usually fix idle hunting. You probably noticed the tip of the screw had a fair bit of caked-on crud on the tip when you pulled the unit off, right?

Here's the public solution in case anyone else stumbles upon this issue. So, I fixed the issue earlier today and took her for a quick spin. I found a replacement J60 AFM, and it was almost new, plugged it in but there was no change. I checked Voltage with the car running and got 12V, and two grounds, so I knew power wasn't an issue. Ran a continuity check from my AFM signal to the ECU, and got lots of resistance, so I tracked the wire down and found it had fused itself to one of my grounds in that protective sleeve. Bypassed it, ran a signal straight to my ECU, and it runs beautifully. No signal meant ECU in Limp mode. AFM Wiring for a J60 (RB20 and RB25 S1), here's what you should see: Black/White - 12V Black/Silver Tag - Ground White - Ground Black - Signal to ECU. Check continuity to Pin 27 of the ECU. If any resistance, fix/replace wire, and voila, Limp Mode problem solved.

If your AFM looks good, check it with a multimeter at the plug. You should have: Black/White - 12V Black/Silver Tag - Ground White - Ground Black - This is your Signal wire to the ECU, check the continuity of it back to Pin 27 on the ECU. If you read the post right above yours in General Maintenance, I was having the exact same issue, not with switching over to petrol, but running it all the time. I even have a video showing my 2000 RPM limit. I have a list of everything I switched over trying to fix the issue, but what it ended up being was my AFM Signal wire was grounding out with one of my grounding wires in the protective sleeve they have going back to the loom. A Continuity check found this, and I bypassed the fried wire for the signal straight to the ECU. Runs like a dream now. No signal from the MAF causes your ECU to run in Limp mode, I'd imagine, which limits it out at 2000 RPM for the engine's safety. Good luck to you!

Update: I forgot to mention that yes, superben, I already tried disconnecting the VCT, but no change. Something tripped when it was turned on, but wasn't being held on by the VCT. As for my Air systems now, I have checked every vacuum line and my IC Piping all the way through for leaks, and I found two probable causes for an improperly running engine, and after fixing them, she runs beautifully now, aside from the ECU cut. First, my external wastegate was impossible to move by hand, and even when removed, getting a good solid grip and really yanking it, it barely moved, and no air puffed out to indicate the flange working like it should. Replaced with new wastegate, much better. Next problem found was by pulling my turbo, and seeing my gasket in terrible condition. One side was completely separated, as well as one entire corner missing, so replaced with new gasket, and my engine bay is much quieter and smoother than what was heard in the video. Lastly, when putting it all back together, I started it up to find no change in the ECU cut issue, BUT, I also saw my MAF was completely unplugged. So, I plugged it in, and to my surprise, no change. Strange way to find the fault, but I now know, despite my cleaning, my MAF is not functioning at all. Side question, is it possible to wire in an RB25 S2 MAF for my S1? Since the pins are different?

Here's my information so far, trying to be as thorough as possible. The engine idles fine, and runs perfect until around 2000-2500 rpms only, then, regardless of load on the engine, (video done at idle), it completely cuts power, it feels like all 6 cylinders shut off instantly. Now, the car stays running, the RPMs will drop down past that tiny threshold and the engine will fire once more, kill itself, and repeat. It feels and sounds like a Rev limiter set at 2500 RPMs. That's a guarantee in any gear, but at the higher gears (I have to limp around only for work, try to keep it parked as much as possible), the engine will break up with any load that causes me to hit useable boost. The major change I had done immediately before, most likely causing this to happen, was I had finally gotten around to fabricating in the VCT solenoid, as I had been running without this whole time. My theory is that, with the ECU now switching my cams for low-end responsiveness, a problem that hasn't been readily apparent is now rearing its ugly head. It's time to start slowly diagnosing, but thankfully I am faily certain the fuel system is not to blame, nor is it my spark, since I have done much work in both areas. This narrows it down to air, but what could possibly be causing this bad of a problem in terms of my air system? Full list of broken down information: 1994 RB25DET S1 swapped into my 1992 R32 GTS-t Type M. No modifications to the engine yet, running stock ECU on stock boost, used RB20DET Harness with injector plug swap method. Troubleshooting steps performed so far: -New Spark plugs, Gapped to 0.8mm, BCPR6ES -Taped/sealed coil packs, strong spark on all cylinders -New Walbro 255 pump, hardwired in via SAU's writeup, No fuel pressure check though, can't find anywhere with gauge immediately -New fuel filter -Replaced FPR with one from known running RB25DET -Took off and cleaned AAC, helped with an idle hunting issue, but not this particular one -Cleaned MAF, shows signs of wear on the filament though, considering replacing -Compression checked at 154+ PSI, all cylinders Link to a video of the described symptoms: http://www.youtube.com/watch?v=e3IofvhHqsw The zoom in on the piping by the turbo was because, just for a bit, I thought I could hear a whistling indicating a huge vacuum leak. When the engine is shut off, I can hear a very audible release of air from somewhere near my Turbo. Possible major vacuum leak? Strangest symptoms I've ever seen for one, but I haven't seen it all so I don't know, frankly. Any tips much appreciated.

Well, I guess you're in luck seeing as how I just did this conversion myself. I opted to go for a Series I RB25, since it is closer to the same style as the RB20. I kept the RB20 loom, hooked to the RB25 ECU. RB20 Loom to a series 2 ignition system is just begging for a whole mess of problems since the two are completely incompatible. The Series 2 has individual ignitor chips in each coil pack, so you would have to do some crafty wiring to make it work with the Rb20 Loom. Now, the reason I used the RB20 loom was because it is almost plug-and-play. What needs swapped over are the Injector plugs. The Rb20 has Top-feed injectors, while the 25 has Side-feeds. So, just chop off the injector plugs from a 25 loom (all 6 will be on their own sub-harness under the intake) and solder them in place of the ones on your RB20 loom (3 will be on the main loom itself, 3 will be on a sub-loom under the intake). If you copy my setup, this is all the wiring fabrication necessary, easy as pie. There are a few things to note on this conversion that I ran into. -Use an RB20 Ignitor and Coil pack loom, this is a must because the RB20 and RB25 ignitors have opposite configurations, the Rb20 ignitor has a 6-pin feed from the ECU, and a 7-pin feed to the coil pack loom, while the RB25 one is exactly opposite. Obviously, this won't work with an RB20 Loom in that case. -The heater hoses hardlines will be much larger on the RB25 block than what comes from the R32's heater core. I don't have any solid fix for this, I happened to get lucky at a hardware store and find a brass pipe fitting that I could clamp on to both hoses respectively to join them. Some people get joiners made, so maybe look into that? -The throttle cable on the R32 is just a slight bit shorter than the R33, so if mounted as-is, the throttle will be open to about 2500 RPM at idle. Two ways to fix this, either nab an R33 throttle cable from a nearby wrecker, or do a little drilling on the metal bracket that secures the throttle cable to move it forward on the intake about half an inch or so. -RB20 gearbox mounts right up the the Rb25, so no worries. It probably won't last behind that thing for very long though. -Motor mounts and starter need to be swapped over to the RB25 once both engines are out, mounts are different, and the starter was just personal preference, so, not really a "Need". -Still not sure how to deal with power steering setup, you should try keeping the RB25 power steering pump, or getting one to put on, because the pulley on the crank for it is a 2 valley pulley, while the pulley for an Rb20 Power steering pump (what I have) is a 3 valley. If you put the RB20 pump on, the RB25 belt will not fit, and the RB20 Belt will hang partway off the Crank pulley, so, your call. -Have to use R33 radiator hoses, R32 ones will not work. Again, wrecker is probably your best bet. -On the IACV, the Rb25 has a different setup from the RB20, so don't be alarmed if you can't find a mate for the purple plug on it. The brown plug actually controls your IACV, while the purple plug is meant for controlling airflow when running A/C. This isn't a problem since, well, the RB20 never had this in the first place, so your R32 won't notice a difference. -I would highly recommend swapping over the wastegate on your Rb20 turbo to the RB25. The RB20 wastegate actuates at just a wee bit higher amount of boost, allowing more airflow, and giving you a free couple PSI with no risks. Lastly, enjoy this conversion. It will breathe new life into the R32 GTS-t that you didn't know these old girls could do, it has been an absolute blast and I haven't even begun to build her yet. Any other questions or hiccups, feel free to give me a shout! Have Fun, and Good Luck!

Yeah, I went through my post and a few more diagrams and realized that mistake. I'm aware resistance deals in Ohms and not Voltage, I first checked all 6 wires from ECU up to the Ignition chip for Resistance (Measuring 00.3 Ohms on all 6) and THEN checked for 12V coming out of any of the 6 wires to the Ignition Chip, and the 3 to the grey plug next to it. So, you're saying that the earth readings at the ECU are correct, so where would my 12V feed to the ignition chip be coming from?

^ Again, jiffo beats me to it. you could pop one end of the multimeter in Pin 19 of the ECU and see if it's grounded through the ECU or a 12V feed through it. If it's grounded through ECU, the other just goes to a constant 12V feed and it activated by ground through the ECU, visa versa if the 12V feed comes from the ECU.

Not a problem, Welcome to SAU!

Yes. The primary differences between S1 and S2 engines are the methods of ignition. S1 uses an ingition chip to boost power to each coil, whilst S2 Coil packs each have an independent ignitor. Internally and mostly external save for some small electrical differences, they are identical. Since it's a bare block, your exterior attachments will all fit on perfectly.

What type of clutch are you using? Stock, yes, your clutch is getting worn. Aftermarkets like Twin Plates and Super Singles and such naturally bite quickly, but a stock clutch should be almost as soft as a cushioned ceramic. Under what circumstances does it shudder? What load/rpm/gear range?

When you say bubbling radiator, do you mean boiling water, or it seems to blow out a bubble in time with your engine firing?

Alright, final check shows me that at the 3 pin grey plug that goes to the coil harness, as well as the 6 pin plug that goes into the Ignition chip, I don't have 12V anywhere, tested all 9 pins, no 12V feed from the ECU with key On, Off, or Cranking. Am I looking at a faulty ECU hopefully?

Series 1 RB25DET with Series 1 ECU and RB20 Harness, Ignitor Chip, Coil harness, and Coils. 00.3 Ohms resistance across all 6 feeds from the ECU to the Chip. But should those be 12V feeds? Because the multimeter shows them as grounds, not 12V feeds.

Alright gents, here's a new one for me, from what I've seen on the forums at least. So, I have no spark in any cylinder for all intents and purpose. I pulled out the multimeter and started at the ECU, checking 12V Power from all my Spark Feeds (pins 101, 103, 105, 110, 112, 114) as well as 12V ECCS inputs (pins 49, 58, 59, 109). All were between 12V-13V EXCEPT for 103, Cyl. 2 Spark, which would come in at around 5V-6V occasionally. I went about checking my ECU spark earths (Pins 1, 2, 3, 11, 12, 13) as well as Main ECU grounds (pins 50, 60, 107, 108, 116) and all checked out as earthing for 12V-13V. So, with the exception of one faulty feed, I had 12V flowing from the ECU to the Ignitor Chip, in theory, but when checking the inbound side of the chip, I had no response on every pin that was supposed to be 12V. So...my question is What Gives? Are just my Spark feeds cut somewhere between the ECU and the Chip? Or am I looking at a faulty ECU? Recap: I have good 12V and earths on all but 1 pin FROM the ECU, but at the plug to the ignitor chip, I have no power. Attached is the pinout guide I've been using. It says the Grounds are pins 101, 103, 105, 110, 112, and 114, But I'm getting a Solid 12V from them, and a ground at 1, 2, 3, 11, 12, 13 and 10.

^^ Keeps you from nearing stall when taking low-speed, sharp turns where there's no throttle but strain on the engine from the PS Pump

Alright, I lifted her up and poked around the gearbox, no plugs hanging, all accounted for. So, I started checking everything for continuity back with a Multimeter, and I found my problem. I'm sort of embarrassed to admit this, really, but it was a very stupid oversight. I had compared my bay fusebox with every other R32 on base here, GTS-t, GTS-4, GTRs, all of them run with no 75A Main Fuse. Apparently, for reasons I don't want to look into, I do need that 75A Main, because I bridged it with a bit of speaker wire and, lo and behold, all my accessories work fine. Thanks for all the input, though, I really appreciate the friendly help!