Slartibartfast

Sounds like you've got the ATX14A transfer. Complicated little blighter, but I'm told they're nice on patchy surfaces. FWIW, the motor only shifts high/low. 2/4 has a clutch pack, which is how the auto mode works. I had a poke around on Nissanpartsdeal and found four different listings for a shift motor for that gearbox. 29010-0W421 (which, weirdly, is listed for the TX10A part-time transfer case, which has to be a typo, because that's a manual box, and as such it doesn't have a shift motor), 29010-0W422, 29010-2W510 , or 29010-2W51A (also listed as fitting the part-time box). That last one is listed as replacing the other three, so I'm assuming they're all functionally identical, and the differences between them were minor revisions or different suppliers or something along those lines. The '05 R51 service manual calls its equivalent transfer case ATX14B. I assume this is a variant of your ATX14A. The shift motor sure does look similar. The PNs I found are 29010-7S111, and its replacement, 29010-7S11A. Given the similar part numbers and function, I assume these just more revisions of the earlier shift motor. None of the earlier part numbers list either of these as a replacement, but that just means they weren't intended to interchange, not that they definitely don't. Naturally they don't tell you what they revised. It may be something that doesn't matter, as it apparently doesn't with the first four PNs. Or it might be something that does matter, like the bolt pattern, or the connector, or the range switch, or the shape of the output. If you can't get the right part, I would compare the TF sections of the R50 and R51 service manuals to see if there's anything obviously different. If the motor's wired the same way around, same test specs, same linkage attached to it, then maybe it's worth taking a chance on--if you can't track down the part that's listed for your application. Worth noting, I was not able to spec a 2000 R50 with an ATX14A and a VG33 on NPD, so it's possible you've got some regional variant that we didn't get here. Or maybe that's what the messed-up listings for -0W421 and -2W51A were supposed to say? In any case, I'm looking at a US dealer's parts lookup, and assuming they apply to your Australian truck. Again, probably a good idea to confirm the part numbers by VIN and/or with a local source, on the off chance Nissan did something dumb. Good luck! Let us know how it goes if you try the R51 part. Might help the next guy.

Guess that would've been too simple. I've heard you can bend lines with a spring and heat, haven't had a chance to try it myself yet. Might be worth a shot if the line is cracked. Good luck with the lower, hopefully the failure is obvious when you find it.

Sounds like the leaky hose you're looking at is the one from the throttle body to one of the idle air valves. Both have coolant plumbed through them to keep them from icing up. Could be the end of the hose has split. Could be it's not the right hose. Given this started when you had the plenum off, I'm wondering if you've switched a couple of lines, and accidentally plumbed vacuum to coolant, so it's sucking coolant right into the plenum. I don't know if there's an easy way to do that on a VG30, but a friend of mine managed it on an Alfa Romeo once. If you want I can get a picture of the plumbing on mine to compare. The lower intake manifold gasket would be my next guess, though it's odd that it would choose now to let go. Might catch it with a cooling system pressure tester. Pump it up, pull the plenum and plugs, and see which runner or cylinder fills with coolant. I have seen a cylinder with a bad head gasket pass a compression test, but that one was just barely leaking. If yours was leaking enough to make the new-pope-smoke, I would not expect the failure to be sneaky. I've heard of oil in the exhaust smoking for a while after the engine is fixed, but I would expect coolant residue to clear up quicker. I had an old Ford make a hell of a smoke show when I warmed it up, but that wasn't oil or coolant--the muffler was chock full of mouse house. It smelled about how you'd expect, and it didn't clear up until I cut the muffler off.

Is that what's in it now? I think you'd be the third person on here who's tried those and had issues.

Yeah, I'm sure it's frustrating as hell. One of those moments where it would really help if these ECUs could show us live sensor data! Running worse over time is likely just the plugs starting to foul. All six fouling the same suggests it's not an injector issue. The new fuel pressure regulator not helping suggests the excess fuel isn't coming up the vacuum line from a bad reg. So either something is forcing more fuel through the injectors than the computer intends, or the computer's getting bad info that's causing it to inject more fuel than it should. Check that the fuel return line isn't pinched or otherwise blocked. Maybe a mud wasp got in there while you had it torn apart? If you can't blow through the return line, then it doesn't matter if the regulator is working, because the excess fuel can't leave the rail. I would also check that the fuel supply and return are plumbed the right way around, though I don't think it would run at all if you had those crossed up. If the fuel lines are OK, try running it with the coolant temp sensor disconnected. If the computer knows that the temp sensor isn't working, it'll guess the engine temperature based on how long it's been running. If this makes it run better than it did with the sensor hooked up, check the resistance of the sensor, and the wiring between the sensor and the computer. (The service manual's troubleshooting for the temp sensor code should tell you which pins to probe for this.) If that doesn't help, plug the temp sensor back in and try the same with the MAF. Again, if it runs better on guesses than it does on sensor data, check everything in that circuit. I know it stalled when you tried unplugging the MAF while it was running, but that may be different it you start it with no MAF vs if it loses connection while running. Check that it codes for the temp sensor and MAF when they're unhooked. If the computer doesn't notice that a sensor is unplugged, then something ain't right with either the harness (current leakage makes the computer think it's seeing sensor data?) or the computer. I would also disconnect the battery for a bit before/after each test to clear any previous codes and self-learning. I would not expect a blocked exhaust to cause a rich condition.

45 is injector leak. The computer does not have a sensor for this. My understanding is that the computer throws this code if the mixture is rich and it can't do anything about it. Check your spark plugs. If only one spark plug is dark, that suggests an injector leak on that cylinder. If all six are dark, something else is wrong. If the injectors weren't seated right, I'd expect vacuum leaks (lean), not fuel leaks (rich). A bad fuel pressure reg (too much pressure or puking gas up the vac line to the plenum) would make sense. I know you've done the coolant temp and oxygen sensors, but I would double check those, and the condition of their wiring (both the harness and the connectors, including the connectors on the valve cover). I had intermittent trouble with my MAF plug for years, and it looked perfectly fine inside. But if felt loose, and wiggling it tended to clear up the problem for a while. 35 is EGR temp sensor, not coolant. I don't see that sensor listed as important to the fuel injection (or even the operation of the EGR system!), so I doubt it's causing your problem. AFAIK it's just there to complain if it doesn't see heat when the EGR is supposed to be operating. Maybe the exhaust temp is low because of the rich condition, and that's enough to trigger the code? I would focus on the other code for now, see if this one clears up when you get the rich condition sorted out. I once tried that on my '93, and it did not like it. My '95 parts car came with a short MAF extension harness with a separate ground lead, so I swapped it into mine, because why not. I have never heard mine run so poorly. I don't know if it was rich or lean, but whatever it was, it was not happy. It ran fine again with the ground disconnected. I have no idea why, or if this is typical. But if yours ran fine before the rebuild, without that added ground, I would disconnect it before doing further testing, on the off chance it's adding another issue on top of the one you're already chasing.

I had Ocean Colour Scene--North Atlantic Drift in mine for a while, but took it out recently. Not their best album. Haven't replaced it yet. I usually use the iPod in the truck. If the iPod counts, today was Weird Al.

Weird. I wonder what the balancer was for, that had the marks 180 out. Assuming the mark you added is correct, and the timing belt is set up properly (you counted teeth rather than trusting the dimples on the back cover, right?), then I'm not sure why it would be fighting you like that. No primary oxygen sensors isn't helping either! Probably running rich. Hopefully that's just a wiring fault.

The cam sensor is in the distributor. I would first rule out the timing belt. Remove the distributor cap, turn the engine, see if the rotor turns. If not, the belt has let go. These engines are interference, but given it's a VG33 (wimpy cams, deep valve reliefs), and it was idling at the time, you might get lucky. If it's not the belt, download the '97 service manual from Nicoclub and go through the troubleshooting for P0340, starting on EC-203.

I've never used a throttle controller! I'm talking about the meddling in the OE system, which I assume the controller is overriding.

Good work getting it back together. Sounds like the distributor is off a tooth. Or is that what you meant by moving the splines? Make sure you're setting it with the engine warmed up. Also check that the balancer hasn't slipped, as Adamzan noted above. Hopefully clearing up the timing wakes it up! EC-23 of the '99 manual says that the knock sensor is not used to tune the engine. It's just to tell the computer if something goes wrong. I relo'd the sensor on mine to the back of the driver's side head. Haven't had any issues with it. I was glad I did it when the sensor failed and I didn't have to pull the intake to swap it out! But I imagine it would struggle to pick up the sound of knocking from the passenger's side, if something did go wrong.

That is a weird one. The 2001.5 service manual has different exploded diagrams for the two different brands of master cylinder, but there's no explanation for why there are two options. The info at the bottoms of some of the Rockauto listings show everything the same between them, with the exception of the size of the mounting holes, which are eleven thou smaller on the Tokico for some reason. (0.343" Tokico, 0.354" Nabco.) I don't see any notes on their brake booster listings for which master they go with, so I'm guessing this tiny difference (eleven thou, or 0.28mm) isn't significant to the size of the studs. I suspect that this is just two suppliers of the same part, but I don't know that, and I can't explain why the aftermarket would bother to reproduce both variants if there wasn't some functional difference between them. Looks like the body of the master should be clearly marked with the brand name, so you should be able to tell which one you've got currently. I would replace like with like, on the off chance it matters. Failing that, I'd trust Nissan's parts lookup, and roll the dice on whichever variant was cheaper that day.

My dad's '03 bucked like that too. His usual mechanic had no idea what was wrong. IIRC it didn't even throw the code, just bucked when he tried to accelerate. Someone else he took it to had seen the same failure before, and replaced the solenoid, and that cleared it up. Looks like this guy had a bad TPS somehow throw this code. Not sure if you've seen that thread already, or whether you already replaced the TPS along with the throttle body. I'd have a look at live data from the TPS, on the off chance, though I suspect the engine in that thread might've been the earlier drive-by-cable--surely drive-by-wire would be throwing more than a swirl valve code if it couldn't tell where the throttle blade was. +1 for going through the troubleshooting in the service manual!

I remember my dad's '03 doing something similar. Pulling a fuse (don't remember which one, this was over a decade ago) and putting it back brought it around temporarily, until it crapped out again. I think replacing the head unit was what got it in the end. I would try unplugging the CD changer, especially if it's dead anyway. See if that clears up the issue with the head unit. Maybe the changer was locked up, and the head unit was waiting for some signal from it? The '03 service manual should offer some system troubleshooting, and at least tell you what all is wired to the amplifier fuse, which might offer some hints.

The threaded ones, or the quarter-turn ones? I've got a warped-to-crap sunshade in my parts car with the quarter-turn knobs.

Good to hear you got it together. Did you swap the Xterra oil filter adapter as well, or work around the R50 one?

I remember reading about an issue with the Japanese starter motors in some '80s or '90s Chrysler? vans. They didn't work in Canadian winter temps, because the grease froze solid, because the engineers had not considered that anyone would attempt to drive a car when it was that cold outside. A similar thing happened with the steering transfer boxes in the early R50s. Nissan had to do a recall (#96V034000) for the grease freezing up in the steering transfer box. The recall said it got so stiff below -30 C that "some drivers would have difficulty turning the wheel."

My '93 behaved very similarly when the connector for the MAF was worn out. It ran fine most of the time, but now and then it would surge at idle, or forget how to idle entirely, especially once it warmed up (high idle when cold masked the problem). Screwing around with the MAF connector always cleared it up, for a while. I finally got tired of messing with it, and replaced the connector, and it hasn't done it since. I don't know that I've heard of an R50 doing that, but that's the first thing I'd check. (Also check for OBDII codes, on the off chance the computer has some idea of what's wrong. Mine didn't, but yours should be smarter than mine.) I have zero experience with LPG (apart from cooking hamburgers!), so I'm no help there. Though, yeah, if it only kicks in over 1300 rpm, I doubt it's related, unless something is very wrong with it.

Yeah, it seems like it would've at least tried to sputter a little at some point if it was flooding. The marks on the timing cover are approximate. The tooth count between the dimples on the sprockets is the important thing. Hopefully nothing got hurt, and the mobile mechanic figures it out!

Good work! Hopefully the bottom one plays ball. Also check Rockauto for connectors. I got a MAF sensor connector from them a while ago. If you have trouble finding a 27mm socket, try 1-1/16".

Nefarious got an R50 engine working in his WD21, with the R50 accessories, and the R50 filter adapter. Info in this thread. I'm guessing the short power steering lines had to be made custom, reservoir moved, alt and power steering pressure switch wiring modified. And it looks like he had to re-engineer the power steering pump mount, probably to make it clear the box. But it is possible! And he seemed pretty happy with the outcome. I'm curious whether a W/D22 oil filter adapter would bolt to the R50 oil pump. Might be an easy way around the problem you're having. There are signs that it may not--the oil pumps for WD22 and R50 have different part numbers, and the seals between the pump and adapter are different as well (R50 has O rings, WD22 has a gasket). But the oil filter adapter flanges on the two pumps look about the same to me, and it looks like the O rings on the R50 are grooved into the adapter, not the pump. So... maybe? Looks like the X filter adapter is still available. That should be what's on my VG33, which is on the floor and half torn apart at the moment, so if you want to compare measurements vs the R50 adapter, PM me. If you want to run the VG30 accessories, keep in mind you'll need a crank adapter and a cut-down VG30 water pump to make it work. I've heard of people running the VG30 crank and oil pump instead of an adapter, and it sounds like that works, but it also sounds like it's a downgrade of both parts. I think I've heard of 300zx guys relocating the oil filter to where that plate is (back to where the filter goes on the VG30). Not sure what they do at the front. Might be something they do when using the VG30 crank and oil pump. Have a poke around on some Z car forums, surely someone's written it up. I vaguely remember someone, might've been Nefarious, having to beat on the VG33 oil pan to make it clear the WD21 front diff. Naturally I can't find the thread now. But, yeah, something to keep an eye on as you're putting stuff back together.

That makes more sense. Too many similar names on stuff!

Maybe? Annoyingly, the manual does not explain why it's like this, just how to test and replace the components. This thread suggests that regulating the cold side helps the engine warm up quicker and makes the engine temperature more stable. I guess the idea is that the engine raises the coolant temp pretty predictably, but the radiator drops it unpredictably, depending on air speed, ambient temp, humidity, aircon, auto trans temp, heat soak, grasshoppers, whatever else. So if you want a stable engine temp, it makes sense to put the thermostat between the biggest variable in the system (the rad) and the thing you want stable (the engine). And when it's warming up, and the lower rad hose is cold, I assume that cold water coming in will help keep the tstat closed for longer, versus a hot-side tstat that only sees the hottest water in the engine. Looks like Ford's Coyote V8 and some GM LS engines use cold-side tstats, too. I did some reading on a Mustang forum, and found some of those guys talking about a difference in design between the tstats themselves (beyond just the temperature rating). Apparently some of the aftermarket tstats they were buying were actually hot-side designs, and acted weird in their cold-side application. Given Nissan's 190F tstat was intended for hot-side use, maybe that's part of why the TSB warned about it cancelling a VG's birthday. Of course that thread was about a very different engine, and unfortunately it was more pissing match than thread (maybe they'd just found out about the cars and coffee memes?), so, handful of salt there. Yeah, mine struggles down there too. It usually kicks in enough to keep the windshield clear by the time I've got the ice off the windows, but sometimes even that seems like a fight. Hopefully the 180 turns that around. Weirdly I've noticed my heater seems to warm around the stereo as much as it warms anything else. I suspect the foam sealing the dash vents together has seen better days. That's probably not helping.

Heat is your friend for that EGR tube nut. Heat, lube, beat on it, repeat. I've had some luck with candle wax for stubborn threads. Heat, melt wax into the threads, try again. Seems to stick around better than PB. I tried just brute-forcing the nut in my '95, and it took some of the threads off the valve, so, yeah, don't do that. If it's a California-emissions truck, an EGR delete will trigger the check engine light.

Hopefully the Amazon ones are good! I had to butcher the hubcaps to clear my Mile Markers. Came out nice enough, but a little nerve-wracking taking a wood router to old plastic. I'm waiting on parts for mine too, at least officially. Haven't gotten around to installing the parts I do have yet.