Slartibartfast

I finally got around to swapping the springs over from the partsfinder. I didn't get as much lift as I expected from them, but they did turn a slight squat into a slight rake, so, that's something. They'll do for now. The hatch corners are now 6'8" off the ground.

Grab the shaft below the coupler with vise grips, have someone work the wheel back and forth (with about the same torque they would if they were driving), and see if the coupler flexes. That'll tell you right quick if the coupler is bad.

I can't find Nissan's part number for an OE one. The diagram only shows it as part of the column assembly. The only options I'm seeing are the aluminum one, some sketchy cheap crap on Alibaba, and the Lares 210. This listing for the Lares shows it cross-refs to four-banger HBs and first-gen X/Fronty, but given none of those have a thriving track day bro market either, I'm guessing you're SOL on finding a poly version. I'm not sure a poly rag joint would feel any different. The stock rubber joint in mine is plenty stiff. There's more play in the steering than I'd like, but that's not where it is.

RE the noise, my first thought is the power steering pump, which is loaded when it's up against its stops. Could also explain why it calmed down once the fluid warmed up. Wouldn't explain the wheel speed connection, though, unless it's just the higher engine speed spinning the pump faster. Wouldn't hurt to check fluid level and condition. Steering angle shouldn't be changing the load on the wheel bearing by enough to matter, not at those speeds. I would be looking for CV axle binding issues (unlikely if the truck isn't lifted) or tire clearance issues before suspecting the bearings. Might also take a look at your steering stops. I don't know how the R50 does its steering stops, but mine are metal on metal (they used to have plastic caps, but those are long gone) and now and then it'll creak like a haunted house at full lock. I just gob a little grease on them whenever I'm under there. I wouldn't expect the leverage to play into the hop, but I guess the harder coils might be changing how the system resonates? Control arm angles from the lift might be factoring into it too. Or even the tires, assuming you're running different tires with the new wheels. Maybe some combination of the compound/tread pattern/sidewall stiffness just doesn't hop like the other tires did?

I'll bet this is a quirk of the Ackermann angle. When you're turning, both front wheels follow curved paths, but the inside wheel follows a tighter curve, so it has to steer sharper. The geometry to make this happen is built into the knuckles (where the tie rod attaches vs where the knuckle pivots). The farther you turn, the more the Ackermann kicks in. This also means that any error in the geometry will show up more the farther you're turned. Anything suspension-related tends to be at its worst at the limits of its travel anyway. I'm guessing the steering angles at full lock don't quite agree on how tight of a turn you're taking, which means one wheel or the other has to slip, which is more dramatic on the polished concrete than it is on normal road surfaces. Strato's wheel offset is an interesting wrinkle to this. Changing the offset wouldn't change the angles, but it would change the curve of the paths they're on--evidently enough to get them closer to where the wheels are pointing. Now that I'm thinking about it, I don't think I've ever driven mine in a parking garage, but I have noticed that it disturbs gravel more at full lock. Probably the same thing going on. In any case, Ackermann is not adjustable (apart from racecar stuff), so I'd file this one under It Just Does That. It's also possible I'm full of crap. But if you're not in 4x, then it's not torque binding. If a tire was hitting something in the wheel well, which would make sense with it only happening at full lock, I imagine you would've noticed the noise or seen the shiny spot. I've heard of the rear limited slip chattering if it's got the wrong lube in it, but I wouldn't expect that to only happen when you're against the steering stops.

At least you had the part on the shelf! Hopefully it holds up. Sucks that they built a bigger truck, with a bigger engine, but downgraded the diffs. The R180 was what the four-cylinder W/D21 got in the front. Spinning up a wheel and then suddenly finding traction does tend to kill things. I blew the front end in our snowplow doing that. Replaced the spiders, washed out the glitter, winced at the marks it left on the bearing races, buttoned it back up anyway. It's held up so far. We run chains on it now, which makes it much harder to get stuck, which reduces the abuse the diffs have to put up with.

Those are the engine computer codes. You want the ABS codes. Separate computer, different procedure. Spelled out on BR-34 and 35 of the '94 service manual that I linked in my last post.

The ABS light on is good news. That means the computer knows there's a fault, and can tell you what it is. Pull the code and it'll tell you where to look. Otherwise you're just throwing expensive parts at what could be a wiring or even hydraulic fault for all we know. BR section is here. The sensor on the rear axle tells the control module (computer) how fast the rear wheels are spinning. (Well, technically how fast the pinion is spinning.) The control module under the seat watches the sensor, decides when there's a problem, and controls the solenoids in the valve block accordingly. The valve block is bolted to the inside of the passenger's side frame rail, about even with the B pillar IIRC, and has a solenoid to block off the rear brakes from the master cylinder, a solenoid to dump brake pressure from the blocked-off rear circuit, and an accumulator to dump the pressure into. Its design and behavior are spelled out in the BR section of the service manual. IIRC replacing the sensor requires removing the flange for the driveshaft. The PD section should cover it if BR doesn't. And, yeah, that's an expensive damn sensor. Are you sure it's the rears that are locking? When my rear brake circuit wasn't working (long story, stubborn air pocket somewhere), the fronts would lock pretty easily, because they were trying to do all the work. A malfunctioning ABS valve block could block off the rear brakes and cause the same issue. I realized my rears weren't doing anything when I jacked up the back of the truck, put it in drive, and was unable to stop the rear wheels with the pedal. If you're locking your rear brakes on pavement, I need to know what kind of pads you're running, because mine do not grab hard enough to do that.

I haven't messed with the round dash cluster much, but when I opened up the dash from my parts car (which also had an inop odometer), I found that the solder joints for the little motor that runs the odometer were cracked. By then I did not have a running truck to test it in (had already pulled the engine out), but I'll bet soldering those up would've done the trick. That is what I'd try. Just be careful while taking it apart, and watch for any bits falling out, in case the plastic gears are what failed. The fuel gauge is built into the fuel pump assembly, yes. The sender, the wiring, or the gauge could be acting up. I would check the gauge while the cluster is apart. Look for any bad joints and make sure the screws holding it in are tight. Failing that, the service manual (probably the EL section) is your friend.

If the ABS light on the dash is on, the computer thinks something is wrong. The BR section of the service manual (free download from Nicoclub) will walk you through it. I recommend filming the flashing light with your phone so you can play it back, because it's not the most intuitive thing to decode. They can code for several different faults, including the computer. Mine coded for the speed sensor. Looks like the light will also come in if the ABS kicks in when you're in 4WD, and that's normal--it's just confused because the drivetrain is locked together through the transfer case, and the ABS can't unlock the front brakes, so unlocking the rear brakes has no effect. If you can't get a response from the diagnostics plug, I guess it could be the computer, though I would check the fuse, the bulb in the cluster, and the wiring (the service manual has a check for this too) before ordering a replacement. The ABS computer should be under your driver's seat. It's the one with the rounded corners, not the box with the hole in the top (that's the alarm). Also check the brake fluid level in your master cylinder. IIRC the low fluid sensor lights up ABS and BRAKE on the dash, but it's been awhile since I dealt with that one. If the ABS light is not on, what makes you think it's not working? There is not much to this system, and it only works on the rear wheels. There is no pump to pulse the brakes. The service manual talks about noise and pedal vibration, though hell if I know how it would do that without a pump. I suspect they may have copied that text from the manual for a different model that used a more advanced system. The only noise I ever heard from mine was a click when the ABS tested itself. I'm on my second WD21 and have never noticed the ABS kicking in on either of them. I ended up deleting the system while chasing another braking issue and have not noticed any changes in handling.

Sounds like you're on the right track. I saw in an SMA video a while back that g/s at warm idle is usually close to the engine displacement, which agrees with your old 3.5g/s reading. A messed-up sensor would explain the trims and the g/s being off. Good luck cleaning the old MAF--and good thinking having a new one on hand.

If you can't pull codes by any other method, it might be worth a shot--but if it hasn't acted up in a while, who knows if the code will still be there.

I played it dangerous and wiped the actual elements. They're delicate, but they're not made of cotton candy, and they're pretty easy to get to on mine. I think you're supposed to just blast them with MAF cleaner, but either I didn't have the right stuff handy or the gunk wasn't budging, so I very gently wiped off the rest. Anything that insulates them will cause the sensor to under-report. Given the limited access on yours, I'd be tempted to see what the ultrasonic cleaner would do about it. Too bad about the smoke machine. Maybe try a lower oil level? I used a proper shop one once, and was not a fan of the smell, but it did work pretty well. Does seem a bit odd to be fogging the engine with glycerine, but I haven't heard of it causing problems.

Looks like some of the VQs use the variable valve timing to do EGR without the external valve. Neat trick. How have you been cleaning your MAF? It looks like the R50 MAF is shrouded in a way that could make it difficult to clean properly. I remember wiping the last of the gunk off of mine with a Q tip or the corner of a rag when the spray didn't get it all, and the filaments on the WD21 MAF aren't shrouded like that. Yours should be spotless given how many times you've been in there, but if that shrouding gets in the way as much as it looks like it would, there could still be something hiding in there. (I wonder if an ultrasonic cleaner would work on a MAF?) The heater is part of the oxygen sensor. Gets it working faster after start-up. You should get a separate code if the heater circuit fails. The primaries are for the air/fuel mix, the secondaries monitor the cats. I have heard of some later-model stuff possibly using the secondaries for more than that, but it doesn't sound like that's the case here. And yeah, it's got an oxygen sensor on either side, so it controls fuel trims for each bank separately. Allows for slightly tighter mixture control, I guess. Wouldn't hurt to check live data from the temp sensor against the actual temperature. Mine behaved similarly. It ran fine at cold (high) idle, but once it warmed up and dropped, it just couldn't hold the lower speed. There are a bunch of DIY smoke machine designs out there if you want to save a few bucks. One I saw recently used a gas station cigar and a cheap hand pump, and it seemed to work pretty well.

A screwed-up mixture might've damaged the cats, or it might just be confusing the sensors, but if the cats were clogged, I don't think a low idle would be your only symptom. I would focus on figuring out the low idle/misfire issue and see if the cat codes go away once the engine is running properly again.

The '02 manual does not spec an idle speed in gear, but in park or neutral, it wants to see 750 +/- 50 if the aircon's off, 825+ if it's on. Sounds like yours is working. Every auto I've driven idles a little lower in gear, so while I don't have a spec for that, I'm inclined to call it normal. Turning on electrical loads or working the steering loads the engine, so it makes sense it's dipping a little more under those conditions. The vibration/stumbling under load, while it's still pretty close to its target RPM, makes me suspect a mixture issue. MrElCocko may be on the right track with the MAF sensor. Yours sounds a bit like how my '93 behaved when the MAF sensor connector was worn out. Sometimes it would idle low at lights, sometimes it would surge, sometimes it would stall completely unless I shifted to neutral or drove with both feet. Wiggling the connector would clear it up for a while. Finally I got around to replacing the connector, and haven't had a problem since. I don't know if the R50 suffers from the same issue, but I would check that the plug feels tight and the sensor is clean. If that checks out, check for cracks in the boot between the MAF and the throttle body, and check for vacuum leaks. Might be worth throwing some fuel system cleaner in the tank in case one or more injectors are a little gunked up. One or two cylinders firing poorly or not at all could explain why it's vibrating so much, though I wouldn't expect that to only act up at low RPM, and I would expect it to throw misfire codes if it was that bad. Probably wouldn't hurt to clean the idle controls, maybe check for signs of the coolant leak those get, but again, it sounds like that system is doing its job. If your throttle body isn't the fussy electric one, maybe give that a clean, on the off chance.

I would check that your aircon drain is clear. Doubt you're running much aircon this time of year, but if water gets in, that's where it's supposed to get out again. Might also be worth removing the cowl vents and checking that the cowl isn't blocked up on the ends and/or rusty around the air intake for the HVAC, which is on the passenger's side.

This guy wasn't impressed. Sounds like it's the same aftermarket stuff with a bigger markup.

I think the WD21 drains into the rocker panel, no idea about the R50. Have you pulled out the wheel arch liner? Might be hiding behind that.

So much room for activities! Buying the hose crimping tool is probably easier than explaining what you need to the guys at the local auto parts place, and probably cheaper, too. I don't remember what my dad paid to have a hose made for our plow, but it was not cheap.

I think the engine just doesn't run well enough when it's that cold to hold its idle speed against the torque converter. Probably just poor fuel atomization. Cold ATF might not be helping, but the stuff is so thin to begin with that I doubt that's the whole problem. I just let it warm up while I clear the windows. Probably easier on the engine anyway. I've read that synthetic gear lube nerfs the clutches in the LSD, don't know about Motul specifically though. Other than that, yeah, can't hurt.

Like an OE Nissan one? That's cool, didn't know that was a thing. Makes sense it would be, though. Yeah, mine's not happy when it's really cold. Takes a few minutes before it'll go into gear without stalling out. Fortunately I've had nowhere to go so far during this cold snap. It was -19F yesterday morning! Can't complain, power's still on on and the plumbing still works.

I haven't done one on a VG, but I replaced one on a friend's Dodge last winter. Not much to it, provided the core plug hole isn't rusted to hell. They're not fun to do from under the truck, in the snow, so you've got the right idea doing it while it's on the stand. The heater I was replacing wasn't very old, so I'm not sure why it burned up. Didn't find any brand information on it. I don't remember what brand I replaced it with, either, but I didn't go with a cheap one, because I didn't want to do it again. IIRC the instructions on the site where I bought the heater said which core plug to replace and which way to point the element for that particular engine. It does a world of good on a carb'd 360.

Jeepers have rubber ducks, this guy has a real one! Dammit, now I want to see this, too. A guy on here turbo'd his VQ and was having transmission slip issues. Probably more hassle than it's worth in a rig that goes places where most tow trucks don't. 12 mpg is rough. Hopefully the gearing helps. I've heard of some rigs de-tuning themselves if they have smog codes--no idea if the R50 works that way, but that could explain a lot. The point of no return is always daunting. If it helps, you've got a group of Pathfinder nerds here cheering you on.