Slartibartfast

I just looked up a few pictures of the R50 balancer and I see the confusion now--the pulley appears to be one with the balancer. I assumed it was the same design as the WD21 with a separate pulley that bolts on. Learn something new every day! Sorry for the confusion. There's more to the distributor than the cap/rotor. There's an angle sensor under the rotor that causes timing issues when it starts to fail, or when the bearings supporting the distributor shaft wear out. Hope your wife's alright.

LOL it could be a whole lot worse. I've seen schematics for smog-era carburetor setups that look like the maze on the back of a kids' menu. Replacing the vac lines shouldn't take too long provided you don't break anything. Just do one line at a time so you don't get them crossed up. The only tricky one is the one to the fuel pressure regulator behind the intake, that one's a braille job. And there should be a sticker on the underside of the hood with the vacuum routing all laid out for reference. I don't remember for sure how much line I bought but I don't think it was more than 6' (and I bought extra because it's cheap and it doesn't stretch well).

Loose connection?

I think fluids for mine ran me about $50, and I used a pop bottle and a piece of scrap hose as a funnel... and the used fluid came in real handy for burning out some tree stumps. But yeah, if you don't want to do it yourself, I imagine a shop could get it in and out pretty quickly. It can be kind of a messy process. I've heard the same about the pan filter, which is why I didn't bother with mine. (Two inch curls of metal... that thing died hard!)

I flushed my '93 through the cooler lines (didn't bother with the pan) at around 230K, and AFAIK the oil I removed was original. It was still reddish on the stick but in the bucket, that crap was brown. It worked fine before the flush, and it continues to work fine a year or three later. If you wait to flush the fluid until the trans is properly worn out and starting to slip, then draining that gritty mess out of there will probably finish it off. Given your mileage and how you aren't complaining of a whole lot more than a vibration, I doubt a flush with the right fluid would hurt your trans. I'm not familiar with this trans shudder issue so I've got nothing to add there. Hopefully catching it early means it's a simple fix.

I think it's one of the weird smaller ones.

I can almost smell that shelf from here!

Not three firing at once--three firing per revolution.

+1 on the dizzy, and on at least checking the condition and tension of the timing belt (especially if you don't know when it was done last). The only way that the marks on the crank pulley will display incorrect timing is if either the keyway between the balancer and the crank has sheared (which finding TDC manually and comparing could identify) or some numbnuts put the pulley on wrong. The pulley has six bolts, so it can go on five wrong ways and one right one. If the pulley's on wrong, the engine wouldn't care but the timing marks would appear at least 60° from where they should be when you looked at it with a timing light. You could also check for top dead on #4 instead of #1. Looking at a picture of a VG30 short block, and thinking about the firing order, I'm pretty sure #1 and #4 should be at top dead at the same time. Three cylinders fire per crank revolution, firing order is 123456, so 1 and 4 must be synched up.

A bad alternator diode can also cause a drain on the battery. I've never messed with the power window system, but I'd check the service manual and see if maybe the power amp for the windows is in the part of the dash where you heard the noise.

Interesting--sounds like your battery's mounted back to front from how mine is.

Any other symptoms? Codes? Any pattern to when this hesitation occurs (wet days, engine cold, engine warm, taking off soft, taking off hard?) If it happens when you take off hard, I'd check the driver's side engine mount and the intake pipe, I've heard of that pipe getting a rip that opens up when the engine rocks under acceleration--which then lets in unmetered air and makes the engine bog out. If it's worse when wet, it could be worn-out plug wires, but I expect you'd notice the misfire if that was the case (and it wouldn't be just on take off). Rattle in 4x sounds like an unrelated issue. I have heard of the guts of a catalyst coming loose and rattling around, or getting jammed in sideways and blocking flow, but I wouldn't expect that to cause a once-in-a-while type issue.

Good to hear it's back up and running with a new rotor! Much better outcome than a stripped timing belt. Loose/dirty terminals suck on any vehicle. A loose terminal can be enough to run the lights, or the starter solenoid (likely that bang you heard), but a small and dirty contact area will have a hard time supplying the starter motor. And don't worry about the sparks from the battery to the body, there's no fuse between the - terminal and the body, so you're not shorting a fused circuit. Making sparks around a car battery isn't a great idea generally (they can go boom if there's enough hydrogen hanging around). You can get a special wire brush tool for car batteries, they've got a round brush on one end for the female part and a Sarlacc-looking end for the male part. Pretty cheap and quick too. I usually give mine a smear of dielectric grease before putting them back together.

Pulling the battery terminal is not a good way to test the alty on a fuel injected rig. The battery does more than just hold power, it filters out the ripples and noise that the alternator makes. Think about it, the diodes in the alty chop 3-phase AC into DC, and the current going to the rotor inside has to pass through sliding brushes, which are always going to give you some noise (especially if they're worn/dirty). The output voltage will ripple and spike. Most computers are not built to deal with that. The Pathy is simple enough that you probably got lucky, but I wouldn't do it again--and I certainly wouldn't do it to a newer rig. Even on an older rig with points/condenser/carburetor, where there's not really anything to hurt, your voltmeter should tell you all you need to know. I've also read that you can fry the alternator diodes by unhooking the battery with it running--not certain how that works but another reason not to go there. You shouldn't need to rev the engine to get the voltage up. If the engine is running, the battery voltage should be around 13-14V whether you rev it or not. This suggests that the alty isn't making enough juice to keep the battery charged. Could be a borked battery, but I'd be surprised if both your batteries were borked--and it's easy enough to check a battery. +1 for checking the connections and belt. If the connections are good, and the belt's not flapping in the breeze, my money's on the alternator.

Lots if info here on all three if you look around. Also check out Nissan Nut's page, he's got a pretty good writeup on what has to be modded to get the 3.3 in there. Off the top of my head, you need the 3.0 oil pan, the oil pump pickup has to be modded to fit, the intake/efi needs to be swapped over from the old 3.0, and the balancer from a 3.0 won't fit, so you're looking at either converting all the accessories to a serp belt (IIRC the arrangement of accessories on an Xterra or Frontier means you can just swap engine and accessories at once and be good to go) or finding some way of putting a V-belt balancer on the 33. That means finding a one-year-only balancer (now unobtanium apparently), swapping the 3.0 crank into the 3.3, having the crank or balancer machined, or running a machined aluminum adapter instead of a balancer. Lots of info on lifts out there. Some guys run 33x10.5 with no lift and minor trimming. Calmini doesn't have the greatest reputation around here and IIRC they don't sell bushings for their idler arm separately. Between that and the price of their kit I'd be looking into other options. A few guys have used steering components from a 2WD Hardbody and seem pretty happy with that.

Got the cup holder welded to the switch panel today. When I skin this thing I'll tie it in at the front so it's a little more solid. At the same time, I think I'll look for a better place for those two power outlets. They're not completely unusable with the cup holder there but there's no way I could fit two cups and a bulky plug in the 12v socket at the same time. I decided that undoing all the spade connectors for the aux light switches each time I took the thing off wasn't the best way to handle things, so I picked up a 12" extension for some kind of computer power hookup. I cut that in half, wired one side to the truck, wired the other side to the console, and done--no more undoing spade terminals by braille every time I take this thing out.

Not an uncommon complaint with the 3.5. My dad's '03 used a quart every thousand miles but only smoked on warm starts. He took to running synthetic oil, not to slow the burning, but because the smoke it made was less visible. I read a few theories at the time, including that the PCV could somehow siphon oil out (changing that didn't help). The catalyst theory sounds like a garbled version of what happened with the QR series motors in the Sentras. Apparently their cats were mounted too close to the engine, got too hot, and fell apart inside, and the EGR on those worked by holding the exhaust valve open to suck exhaust back into the cylinder... along with bits of the disintegrating cat, with predictable results. I haven't heard of anyone proving a similar issue with the VQ. They do have power valve screws that have been known to work loose and fall in, but IIRC only the auto trans rigs got those. Bad valve seals sounded most likely to me but I never got to tear the POS apart and find out. But apart from sucking back a quart a week, and a (likely unrelated) issue with something on the swirl valve circuit making the drive-by-wire act up, it ran fine. Pulled hard, fuel economy was normal, no unusual codes. The dealer suggested that it would probably keep running just fine so long as he kept adding oil. I would expect the oil in the exhaust to kill the catalysts eventually, but so long as you don't let it run dry, I wouldn't expect the engine itself to fail. If you're looking at secondhand engines, check compression. My dad considered an engine transplant and discovered that the VQs in the local yards all had an unusually large variance in compression from one cylinder to another.

The tank doesn't have a sump for the pump inlet, so consider how wide it is and how the pump isn't totally bottomed out and you can see how there's a fair amount of fuel that the pump can't suck up. I'm not sure if this is a feature to keep sediment away from the pump or if it's just lazy design, but either way, the pump will run dry long before the tank does. If mine gets really low I'm not surprised to put 16 gallons in there. My gas gauge works but I trust it about as far as I can throw it, and usually consider anything over 250 miles to be pushing my luck. I managed 300 once in my '95, followed almost immediately by running out of gas maybe three miles from the gas station. That was when I discovered the existence of a godawful little spring-loaded flap that lives in the gas filler and makes it a royal pain to fill if you don't have a long spout on your gas can or a long screwdriver to jam in there. I had neither and ended up with more gas running down the quarter panel than going into the tank. If I ever have the gas filler out of my '93, that little flap's coming out.

Interesting. Good to hear it's working!

Hmm. Does sound like a fault in the door lock timer, unless the design changed between your '90 and my '93. I lock either front door by pushing the knob down and the rest of the doors lock at the same time. The solder joints in that timer are apparently a common issue. It's in the passenger's rear fender, accessible by pulling out the trim around that rear hatch latch and then the lower plastic side panel. Little box, grey IIRC, should have a sticker on it that says door lock timer.

Nice! I've gotta look into getting a scope one of these days.

The switch doesn't light up. I wouldn't be surprised if it was the switch, especially given how much crap drops down into that panel. If you manually lock the driver's or passenger's front door, do the rest of the locks lock automatically? If they do, I'd lay money on the switch. If not, I wouldn't rule the switch out, but I'd be more suspicious of whatever module controls the door locks. (That's not a part of the service manual I've had to dig into yet.)

I found myself in the shop this afternoon with a brand new Hazard Fraught chop saw to try out and decided it was time to get back to this one. I cut a couple 3" lengths of the 3" tube, slit them, spread them until they were closer to 3 1/4" and would fit a 1-liter bottle snugly, and then siamesed them together. This ended up being a little too tall, so I cut it down to 2 1/2" with the chop saw and then closed in the bottom with sheet metal. And here it is test-fitted. I'm not 100% sure how I'll mount it at this point but I'll probably just notch the switch plate, weld it to that, and then start building up the sheet metal around it. I'm thinking I'll include another single holder on the passenger's side up by the dash. I was thinking of putting a couple of holders on the back of the console, but then I sat back there. I had forgotten how little room there is back there, especially with the front seats pushed back. It's a good thing a few of my friends are short. It's also a good thing they don't seem to mind holding cups, because there's no way the back of that console is getting a cupholder. I guess a cup of liquid next to a power outlet next to somebody's foot wasn't likely to end well anyway.

I haven't had one fail on me yet, but from what I've read, the classic failure mode of the VG dizzy is that it usually works when it's cold, then starts running like crap as it warms up. Some people report finding red dust inside the dizzy at the same time, likely from the dizzy bearings starting to go. The check I've read for the bearings is to take the dizzy out (make sure you know which way it was pointing so you know how to put it back), spin it by hand, and see if it suddenly stops spinning like it's catching on something. IIRC someone had the screw that holds the rotor on fall off and bounce around inside, but that should be fairly obvious once the cap is off. Sounds like the cap/rotor have to be pretty knackered before you notice any issues there. One or two guys have reported the engine trying to idle counterclockwise after they've shut it off, and IIRC at least one of them said a new dizzy stopped it--I doubt that's a common fault though.

Not bad, especially for winter. Leave the O2 sensors in, the computer needs them to set the fuel mixture. The secondaries, not so much, but you'll still have a code all the time.