Slartibartfast

Kind of depends on how much of it's broken, how original you want it to be, and the tools at your disposal. I broke a stud off of one of my hangers, and found that I could just unbolt the broken hanger from the frame and weld a new bolt on where the stud used to be. The bracket that held it to the exhaust pipe was shot too, so I just welded up a new one out of scrap metal from a bed frame. I think it turned out pretty well; I actually like it better than the pipe clamp sort of deal that the exhaust shop put on there in the first place. Can you get a picture of which hanger/hangers you're looking at?

I still doubt a clogged cat. Seems like it would run worse the higher it revved rather than sorting itself out around 1800 rpm like you said. If the cat's hot enough to glow, that suggests that there's a lot of unburned fuel in the exhaust, which the catalyst is burning (as it's supposed to). That kind of heat probably isn't good for it, but IMO it points to a problem other than the catalyst. Normally I'd say it's got a misfire, so it's blowing unburned fuel/air right into the cat, but your recent tune-up and the fact that it runs alright at speed kind of shoots that down. It could be a sensor screwing with the mix (MAF, coolant temp, or O2). IIRC the ECU is supposed to be able to guess sensor values well enough to run without them, so you might try unplugging each in turn to see if it idles better guessing at values than it did listening to the sensors (which would indicate sensor or sensor wiring issues). The idle air control stuff does cause idle problems from time to time, but I've never heard of it making the cat glow. My pet theory is that you have an injector or two that are leaking internally. This would show up most at idle, where very little air/fuel are going through the system, and any extra fuel is going to have a big effect on the ratio. At higher speeds, there's more air/fuel going through anyway, so the leak doesn't make as much difference. At idle, though, all that additional fuel won't burn properly, making for rich exhaust; the ECU will see this as a general rich condition (it only has one oxygen sensor) and lean out the mix; the other cylinders will run lean, contributing air to the exhaust; and the fuel will meet the air in the catalyst and burn like crazy. Meanwhile, your engine sputters and chokes and tries to run with a couple cylinders pig rich and the rest starving for fuel. I would have a look at the spark plugs and see what they tell you. White crusty plugs are lean, dark or wet plugs are rich. Your new plugs might not have been in there long enough to tell you a whole lot, but it's the best way I can think of to track this down, assuming it is what I think it is.

Madhackish, where did you find the steel lines? I looked around a bit, but I couldn't find a kit that would work with rear disks.

Good to know I'm not the only one who had issues! I bought one of the open-sided sockets just for this job, and it was still rounding. A mechanic I know suggested cinching a hose clamp down around it to prevent it from spreading and slipping like it was. At the time, the best I could think of was welding the socket to the sensor, which succeeded in breaking the top off... and with the ceramic out, I was able to crush the base of it enough to break the corrosion on the threads, then back it out with the vise grips.

Nice! Reminds me of the 4Runners where the rear window rolls down into the hatch. What do you have in mind for the wiring? I'll bet a power window rocker switch would work pretty well, the latch might take some playing around with though so it catches/releases properly. The glass can probably handle it, so long as you don't forget and try to shut it by hand from the unsupported side.

How did you manage that?

Sounds like it had a few issues! Hopefully fixing those does the trick. Leaking valve cover gaskets are dead common, and tightening the valve cover screws down often helps. Not sure exactly what you're talking about, but that is when it's supposed to go into overdrive. Do the revs drop quite a bit when it does this?

That sucks! I'm not entirely familiar with the valve in question, but I have heard that carbon from the canister can get into the evap valves and cause problems there, especially if it's overfilled when gassing up. Maybe bits of charcoal jammed up your old one (or just kept it from sealing properly), and are trying to do the same to the new one but haven't fully stopped it up yet. Check the can, blow through the lines and see if anything comes out?

Maybe that's the trick. I was working with the exhaust cold.

I replaced my oxygen sensor tonight. I didn't figure it would take too long. The oxygen sensor had other ideas. I'm pretty sure this job isn't supposed to require a welder, a slide hammer, vise grips, and six hours of my life. And no, it wasn't broken in half when I started. On the bright side, putting the new one in was pretty simple.

The service manuals are here: http://www.nicoclub.com/archives/nissan-pathfinder-factory-service-manuals.htmlShould be in the MT section. As for the power loss after the distributor replacement, sounds like the distributor might've gone back in one tooth off.

The zipping noise is interesting... sounds like something broke/came disengaged and the zipping is the broken parts rubbing against each other. I agree with B on it probably being the tranny, the transfer cases are pretty solid. You might take a look at the external linkage for the case though, on the off chance that something came loose there. The service manual has a bit about how to read transmission codes with the "power mode" light on the dash (AT section). I don't know how much it would tell you, but it's worth a shot.

Open circuit suggests that the solenoid coil is burned out, the connector isn't making good contact, or a wire is cut somewhere. Could very well be the coil in the vent valve solenoid. I would run a continuity check on that component.

I do notice a lot less lifter clatter at startup since changing to 5W30.

Maybe Nissan wanted to make sure the starter didn't dry out. Looks like I spoke too soon, it still lingers a little on cold starts (must be the thinner oil). It's still nowhere near as bad as it was before, though.

I'm not sure exactly what sets that light, whether there's a separate switch in the fuel level sender or some circuit that sets the light if the signal drops below a certain point. The FSM might be able to help you there. I've run mine dry without the light coming on, and when the light has come on, the fuel pump didn't quit.

Just an update on this, the oil filter was definitely the problem. Changed it recently with 5W30 and a Union Sangyo filter from work and there's no more lingering oil light. No more Napa filters on this rig! I meant to hack open the Napa filter and see what was wrong with it, but it was late and I forgot.

Good to hear it's fixed!

If you're gonna get a junkyard tranny, you might as well get one of the later transmissions from an Xterra (there's a thread on which ones will swap in). They bolt right up and are built stronger.

I can't really tell the difference driving it, but I did an experiment once with yanking on the open tire carrier (leverage!) with the shocks on/off and did notice some change in how much/how easily it bounced.

You definitely need some kind of funnel. I thought I could get away with just pouring it in and splashed it everywhere. I didn't have the special funnel, so I took a plastic root beer bottle, cut the bottom off, drilled a hole in the cap, and jammed a piece of tubing in there. So long as I held it up it worked alright. Having used the proper funnels since, get one of them, they're much nicer to work with.

For eight times the price of an aftermarket radiator, it had better be hard to install.

Either you guys put a lot more gas into corners than I do, or my LSD is getting weak. I don't think I've ever had the rear end on mine step out when I didn't mean it to, except for a little shimmying once in snow on a mountain pass with summer tires. I've had more issues with understeer than I have with oversteer. I notice you're both running five-speeds, and I've got an autotragic. Maybe that makes it easier to break the rear end loose under power.

I've read speculation that the cooler in the rad helps bring the tranny fluid up to temp more quickly on cold days, but I've never heard of someone losing a transmission from it being too cold. The cooler in the radiator is supposed to transfer heat between the tranny fluid and the coolant. The problem is that the little tube or whatever's in there cracks and transfers coolant into the ATF, causing the strawberry milkshake of death. You could replace the radiator, if you trust that the new one is designed better and won't suffer the same fault. I think most people just unhook the trans lines from the radiator and hook them to an aftermarket cooler instead. (Probably best for towing anyway.) I don't know if blocking off the lines to the stock cooler would be necessary or worthwhile. IIRC the reason they call it a bypass is that some R51s come with a real tranny cooler plumbed in line with the one in the radiator; with that setup, you can bypass the cooler in the radiator and still have the other one. Whether that cooler is enough to tow a camper is not a question I can answer.

The ECU has five different modes of operation, and it flashes both lights together the number of times for the mode it's on, cycling through them until you select one. So they flash once for mode 1, pause, twice for mode two, pause, three times for mode three, and that's when you stop it to read the codes. I turned the screw again on mine, I assume you move the switch on yours. That should make it spit up its codes. Keep in mind that a bad sensor or sensor circuit won't always throw a code. If the computer isn't getting usable data from one of its sensors, it can (for some sensors) disregard that input and try to work around the problem. If it gets data, but the data is wrong, it'll try and adapt to whatever condition it thinks it's up against. If it's trying to idle in your driveway in Arizona, but a knackered sensor or faulty wiring tells it that the cylinder head is thirty degrees below zero, or the throttle is wide open, or something else along those lines, it's gonna have a bad time, and it probably won't be able to tell you why. Ain't OBD1 fun?