Slartibartfast

That's not a vacuum line, just a breather. There's no center axle disconnect on these. If the input spins, the outputs should spin too. Again, it's an open diff, so it may only spin one side depending on which hub is locked/which side has more drag on it. I would be very surprised if the diff was bad. My money's still on the hubs, or maybe a CV axle. Should be easy enough to check, though. With the truck parked in 2H, slide underneath and turn the front driveshaft by hand, while watching the flanges that the CVs bolt to. If one or both outputs do turn, then it's not the diff. If neither flange turns, and the driveshaft just sorta freewheels, then, yeah, that's gotta be the diff. To check the transfer case, put the shifter in 4x and try turning the driveshaft again. If the transfer case is working, the driveshaft won't turn. If they both check out, I'd take a closer look at the CVs and hubs. Sounds like you party a lot harder than I do!

Hopefully the corrosion was what killed the link. Gotta wonder what popped the locks fuse. There is a power lock in the tailgate, so, yeah, could be something going on between the two. Again, I would check the wiring between the roof and the hatch. Relay sounds OK. Should be some resistance across the coil, continuity across the normally closed contacts, open across the other two. If you apply 12v to the coil, the normally closed contacts should be open, and you should have continuity across the other two. Are you testing the switch while it's plugged in? Testing components while they're hooked up is a great way to confuse the hell out of yourself. If it tests good when it's unplugged, the switch is OK. The only tests I'd do with the switch plugged in is check for power across it (assuming you can get to it without putting your fingers in the way of the linkage). If the switch is closed, and you've got significant power across it (I would expect millivolts, but not many of them), something ain't right. If in doubt, temporarily bypass the switch (jumper leads work great for this) and see if that clears up the issue. Is red/green getting 12v?

Black at 211 is indeed ground. Blue/black should have 12v when the key is on and the wiper relay is not energized, so that sounds right. White/blue should have 12v power with the key on and the hatch glass closed, so, yeah, 9.1v says you have some investigating to do there. It gets power from the same place blue/black does (green/red), so you know the wire coming back from the dash is OK. I would check the glass hatch switch (in the latch). If it's closed, but you're only getting 9.1v after it, yeah, something ain't right. Test for the missing voltage across the switch. If the switch is open, and you're seeing 9.1v after it, it could be backfeeding power from elsewhere in the circuit. I don't know that it should be doing this, but I also don't know that it shouldn't. If white/blue gets 12v when the hatch is shut, I would note the weird voltage but not chase it unless I run out of ideas or something else makes it make sense. If it's 9.1v regardless, that's a problem. I would expect this problem would stop the wiper, not make it run constantly, but I don't know how the amp works. I guess in this context "wipers" is vague as hell, sorry about that. I meant the contacts in the motor that keep it powered until it reaches its home position. There's a little metal finger that spins with the wiper crank, and a C-shaped track that it runs on, with the gap at the home position. So if you turn the wiper off when it's not in its home position, this setup is what keeps it powered until the wiper is home (and the finger finds the gap, breaking the circuit). Looks like this switch hooks to black (ground), blue, and blue/black. It's the pac-man looking thing under the motor symbol in the diagram on EL-70. The pulsed power you're seeing on blue makes me think this is probably OK. EL-91 shows where the amp and relay are located. My money's still on a wiring fault, but, yeah, I wouldn't be shocked if it took out the amp, too. The thing that's confusing me is how it took out a fuse link but left its own 10A fuse intact. That makes me think another circuit may be involved--and, yeah, depending on what shorted to what, that might've screwed up the amp. Or maybe the fuse link was just old and corroded and failed under normal load, though I'd be surprised if under-voltage took out the amp. I would be tempted to give the wiper amp a good thwack with a screwdriver, on the off chance that frees up a stuck relay contact and brings it around--but I would be surprised if this fixed it.

I've got an '89 service manual on Dropbox. EL-70. Hatch guts should be the same AFAIK. If it doesn't match up, let me know and I'll check my paper copy of the '87. I screwed around with the linkage in my rear hatch once, maybe ten years ago. It wasn't acting up, I was just curious and in the neighborhood anyway (messing with the switch for the rear dome light IIRC). I remember the mechanism being a little more complicated than I had expected. IIRC the wiper has two resting positions, and only one of them hits the switch that allows the electric rear hatch popper to work. If the manual doesn't get you there, let me know and I'll open mine up and remind myself of how it's supposed to move. Do not adjust anything until you know how it all works. The switch did not likely adjust itself between when it worked and when it didn't, so messing with it will probably just make more work for yourself once you find what's really wrong. This sounds like a wiring fault to me. I would check the wiring between the hatch and the body for broken wires and cracked insulation. Could explain the burned fuse link and the motor getting power when it's not supposed to. Failing that, I would check the wipers in the motor that keep it going back to its home position, but it sounds like you did that already, and I would not have expected those to take out a fuse link. And, yeah, wouldn't hurt to check the switch as well, though again I don't think that would've killed a fuse link.

I have never found a timing belt time interval from Nissan, but it looks like other manufacturers spec less than ten years (some as low as five). Probably best to swap that belt out before it realizes that 2004 was 20 years ago.

back! 3k rev limit means it's in limp mode. I've got an '89 service manual on Dropbox, EF&EC section is your friend. Start by running codes.

Mine is plumbed like this: transmission cooler supply line --> stock cooler in the radiator --> external cooler --> Magnefine filter --> transmission cooler return line. Probably would've made more sense to put the filter before the coolers. Some folks here used to recommend bypassing the stock cooler in the radiator. They were said to clog up. I haven't heard anything about that in a while, and suspect that dying transmissions were clogging coolers, not the other way around. My transmission was fairly new when I did mine, and I figured more coolers is more better, so I'm running both. I don't think I've heard of one of these having the Strawberry Milkshake Of Death issue that the R51 Pathfinders often did (failed cooler mixing ATF and coolant into an expensive mess). Here are three old threads about how to mount a cooler and which one to use. Unfortunately the pictures on the last one are long gone, but the discussion may still be of some use to you.

Sounds like it's in good hands! Hopefully it's an easy fix. And yeah, not like Redpath's crank! That's what I was afraid you were gonna find.

Yeah, that's not good. Could be the key, though I'd be surprised if it just freewheeled with that busted. I've also heard of VG30 cranks breaking between the timing sprocket and the balancer. Hopefully it's not that. Grab the pulleys and see if the whole deal just comes off. I've heard of people welding and grinding a damaged keyway, or welding in the key, or using JB weld or Loctite and trusting the crank bolt's clamping force to do the rest. I don't remember if any of these methods worked, but I do remember seeing a few mentions of repeat failures. These may have been from people installing a new key in a wallered keyway without doing anything to stabilize it, though. And yeah, if the crank turns out to be buggered, might as well get an upgrade out of the job. The 3.3 crank snout is bigger. This is a good thing, but also a problem--it's why you need to run the donor's belts/accessories, or get an adapter to run the V belts, because the 3.0 balancer won't fit over it.

Sudden loss of power has me thinking timing. Is yours the 3.3 or the 3.5? (Not sure when the 3.5 started down under.) The 3.3 has a rubber timing belt. IIRC they run like crap a tooth out, don't run two teeth out, and will eat the valves somewhere past that. The 3.3 is a little less interference than the 3.0, so you've got a decent chance of the valves being OK, but I would not push that luck by starting it again before confirming that the belt hasn't skipped a tooth at the crank. Roll the engine to TDC, pull the covers, count teeth between the dimples. 40 between cams, 43 cam to crank. If it's the 3.5, I've got nothing. My dad's Tundra jumped time a while ago because a mouse found its way in behind the timing cover. The engine got lucky, just needed a wipedown and a new belt. The mouse was not as lucky.

Sounds like a question for the rebuilder.

Should be the same as '89, service manual here (Dropbox link). Don't remember where I found it or I'd link you there instead.

Yeah, I hear you on not wanting to throw expensive parts at it on a hunch. I don't know how good aftermarket VQ injectors are/aren't, but I remember Cuong Nguyen had a hell of a runaround with cheap injectors causing problems on his VG. I think he ended up getting a set of OE ones from the wreckers. Being a cheapskate myself, I'd probably try and swap the injectors from hole to hole before buying new ones, but I also understand not wanting to have to take it apart a third time if it turns out the injector is the problem. I would be tempted to also check under the valve cover while it's torn down, but that's mostly because I just opened up a misfiring Dodge where the roller decided it was done and ate the cam lobe. I haven't heard of a VQ doing that either, and I imagine the noise would've tipped you off if yours somehow had. Hopefully it ends up being something simple. Good luck!

The MAF is a good thought, and an easy one to check if you've got a half-decent scanner. Could explain the hard starting, too. That said, I wouldn't expect it to only cause problems on one cylinder. The service manual offers a little troubleshooting for misfire codes. Might be worth a read. Looks like you've tried most of what they suggest, though. I would follow the compression test with a leakdown test. When the head gasket let go on my neighbor's Toyota, the compression still tested fine, but when I applied shop air to #4, it bubbled out of the radiator. (I didn't have a leakdown tester at the time, so I stripped the compression tester down to just the hose, and stuck the air nozzle in the end.) It's probably not the head gasket--I don't remember anyone else on here having a head gasket let go on a VQ, and I imagine you would've mentioned if it was losing coolant--but it's still worth ruling out. When you replaced the plugs, did #1 stand out from the others? Color, deposits? Might give a clue if it's a mixture issue. When you installed the injectors, did they all go back in the same holes they came from? And did you flow-test them after cleaning them? If #1 has its original injector, untested, I would not rule it completely out yet. Are you sure what you're seeing in the exhaust is fuel? My dad's '03 burned an alarming amount of oil, especially on warm starts, though I don't remember it throwing misfire codes. Have you checked your your power valve screws? Long shot, but if one of the butterfly plates fell in, I can imagine it getting stuck in front of an intake valve or something.

A friend and I did that on his Blazer. Got a bucket with measurements on it and poured in the same amount that came out each time. It would've worked better if we'd kept better track of the level in the bucket between rounds, but we got there in the end, and we didn't overfill it like I did mine. I did a bunch of work to the truck right after I got it, including the trans fluid, so I never really got a baseline for how it shifted before. After the flush, it shifts pretty well, apart from a lazy 1>2 shift under load. It hasn't gotten worse over the last 26k miles, and the transmission is still alive at 257k miles, so I'm not complaining. While you're in there, consider adding an external cooler, especially if you wheel or tow (the hotter the fluid, the faster it degrades). I also plumbed in a Magnefine external filter while I was in there. I don't know that it's doing much, but there was a little metallic shimmer in the old fluid, so I figured adding an actual filter was a good idea.

If neither CV spins when the driveshaft spins, something is very wrong with the front diff. That said, it's an open diff, so if one hub is locked, it'll spin up the CV on the other side rather than doing anything useful. The diffs are also hell for stout on these, and surrounded by weaker components, so, unlikely failure. The fuel gauge knowing about the outside temperature is weird. Not sure which way to send you on that one. I'd probably check under the access plate in the back first (under the rear carpet), see if there's a bunch of mud around the wiring connections that's shorting them out when it's wet or something.

Nice find! It's been too long since I built a model kit. Funny that the box lists the engine specs like they're something special. I'm also wondering what mistranslation led to it having a "fog roof."

Yeah, I think that's the same knob that's on the US trucks with the all-mode. Anyone here with the all-mode box want to check the numbers on your module? Long shot that the US-spec computer would be the same.

I have no idea what fits what, but I did a little more poking around. I found a whole lot of modules that start with 33084, for a bunch of different vehicles and transmissions, but none with your full PN. Looks like 33084 says what it's for, and the rest of the part number says what it fits. I couldn't find any transfer modules listed for an '00 R50, or any year R50 that I searched, which is weird. But yeah, given how many flavors there are of this thing, I'm guessing the numbers do need to match up. IMO you've got two options at this point, and both involve scouring wrecking yards. Option one, find the same-ish year R50, same engine, same transmission, same transfer case, and hope it's got the same module in it. Option two, find an R50 with the TX10A manual transfer, and grab that, the shift linkage, the center console, probably the trans tunnel plate too if they're built that way, and convert yours to a transfer case that doesn't need no stinkin' computer. I don't know for sure that having that module gone wouldn't take something else out, but if it drives around as-is, and everything else seems to work, then hopefully it won't mind. I am still assuming I know what transfer case you've got. Does the knob have an "auto" position? I haven't heard of any other transfers being used on these, but Nissan does seem to enjoy changing weird things for no apparent reason.

Oof. Yeah, that's deep! You're lucky if that module's the only thing that responded poorly. I have not heard of any other model using the ATX14A automatic transfer (which I assume is what you have, given it's got a control unit). I've seen two variants of that, one with just a heater knob on the dash for 2h/auto/4h/4l, and one with a knob or buttons for 2/auto/4 and a manual shifter for high/low. I imagine you'll need to match the donor to the control style that yours has to get the right module. The case numbers didn't get me anywhere, but might be something you can confirm against a possible replacement at the wrecking yard. Hopefully they're not coded in or something dumb like that.

It is possible to fit the D21 sealed-beam headlights. You will need the buckets, grille, and corner/parking lights, and you'll need to change the light plugs. (It's generally recommended to build a relay harness for these rigs anyway, both to preserve the switch and to make sure the lights are getting full power.) I'm not crazy about the look, but it does open up a lot of options for better lights. I've seen people swap LED pods in place of the factory fog lights. Could be done cleanly if you can find the right size of pod. I had Hella 500FFs on my front bumper for a while. They were great when they were aimed right, but they wouldn't stay aimed right. I've got a cheap lightbar now, which does not have that issue. It's not a 1:1 replacement for the Hellas (it's more of a flood light), but it's good for spotting deer off to the sides. I've got it wired so it only works with the high beams, so I don't have to deal with two separate switches when there's oncoming traffic. For the hood vents, sounds like you're talking about something like Raptor grille lights. I haven't seen it done, but I don't see why it wouldn't work. Might be tough to make it look intentional, though. There are holes all the way through the vents, but they're about the size of coin slots, and the hole in the hood behind them rests against the rubber strip that goes over the core support. I think my door seals let in more air than the hood vents do.

Pretty much just R&R. The Allen bolts may fight you, mine were stuck pretty good. The service manual wants you to select new snap rings of the correct thickness to set the end-float on the CV axles (and the tension on the seals at the back of the hub), but I don't think anyone actually does that. Hawairish started a thread comparing different brands of hubs. Even the cheap-looking ones he looked at seemed pretty decent inside. The OE manual hubs are supposed to be the strongest, but good luck finding a set of those. Warns are popular. I'm running Mile Markers on mine, and apart from the chrome plating being crap, they've been great. I also posted a video in that thread (second page) from when I replaced mine, showing what's involved.

Looks like I was wrong about the knock sensor, and Peejay is correct--code 34 is for electrical faults only. The computer does not throw a code for actual knocking. The electrical checks for the knock sensor are pretty simple. Might as well chase those down while you're after the other three. I suspect you'll find a common fault behind all four--maybe a shared ground that's come loose/corroded, maybe harness damage. Come to think of it, the knock sensor grounds to 35M. The MAF grounds to 35M. The transistor for the coil grounds to 34M, which is right next to 35M. If those are loose/corroded/chewed, that could be three of your four codes right there. The harness diagram in the '90 manual is just this side of useless (they tried to show three different engine options in one diagram). The knock sensor diagnostics in the '95 manual show 34 and 35M near the coil, but I don't see any grounds in that neighborhood on my '93. I think 34 and 35M might be the two at the front of the upper intake, on either side of the Allen bolt, near the coolant temp sensors. Loosen, clean as needed, retighten, clear codes, see if that gets you anywhere. The injectors are grounded through the computer, so they shouldn't have anything to do with those two ground points. The same mouse might've chewed on that harness too, I guess. Or maybe the previous owner parked it because an injector was dead. Looks like your understanding of it was bang on! But here's the long version. The knock sensor is piezoelectric, similar to a guitar pickup or a microphone. It allows the computer to "listen" to the engine. If the computer "hears" pinging/knocking, it retards the ignition timing to prevent engine damage. It does not set a code when it does this. I don't know how long it waits to reset the timing back to normal afterwards. EF&EC-72 ('90 manual) says that code 34 is set when the knock sensor circuit is open or shorted. The diagnostic procedures for code 34 ('90 and '95) and P0325 ('97) are just electrical checks on the sensor and its wiring. Looks like the computer also pulls timing when that code is set. I guess it's playing it safe while it can't tell if the engine is pinging or not. The '90, '95, '97, and '03 manuals all make clear that the knock sensor is not used in normal operation. It's just there to save the engine when something else goes wrong. Sorta like a smoke detector.

I've never found a service manual for the Terrano. But one of the guys (pretty sure it was Ekim Naelcm) on the FB page made an R50 auto trans work in his Terrano, and IIRC all it took was swapping over the bellhousing and having a torque converter made, which means it's (at least a variant of) the same RE4R01A that's in the North America-spec gas-engine trucks. The '95 US manual specs 8.5 liters (9 US quarts) for the 4WD, 7.9 (8-3/8) for the 2WD. It calls for "Genuine Nissan ATF" or Dexron II. The R50 (which has an upgraded variant of the same slushbox) service manuals spec Nissan Matic D, so I assume that's what "Genuine Nissan ATF" means. I used bottom-shelf generic dex-merc in mine and it didn't seem to mind. I flushed mine by putting the cooler lines in a bucket, running the engine until it stopped pumping brown fluid into the bucket, adding fresh fluid through the dipstick tube, and repeating that process until the fluid coming out was recognizable as the fluid I was putting in. Dropping the pan looked like a PITA, and I'd been told that the filter is more of a screen than a filter anyway, so I didn't bother with it. I have since seen a picture of a trans filter full of what looked like clutch material--not sure what else was wrong with that transmission, or how common that is. Might be worth checking the filter (and wiping the sludge out of the pan) for peace of mind if nothing else. Be careful filling the transmission. The level changes a lot as it warms up, and you're supposed to check with it warm. I thought I had it close, warmed it up, and had to drain about a quart to get it back down to the mark.

Sounds like the hubs weren't locked. The stock hubs on these are supposed to lock automatically, but they're not known for their reliability. Manual hubs are a huge upgrade and an easy mod.