Towncivilian

A new OEM one is only $40 here: http://www.courtesyparts.com/34980-park-position-switch-pathfinder-r50-02/1997-07/1997-33lat-09/1999-01/2000-33lat-p-203091.html?cPath=4700&

http://www.nicoclub.com/FSM/pathfinder/2000_Pathfinder/ To save a copy of the FSM, right click -> Save As on every PDF, save them into a single folder, then use fwd.pdf to navigate.

The transmission is designed to downshift when you floor it. P0507 doesn't exist. You must mean P0705 PARK/NEUTRAL POSITION SWITCH. There is a fairly lengthy diagnostic procedure starting on page AT-100 of the FSM. I believe this is the PNP switch if you need a replacement.

This is unrelated, but it would be more beneficial and less wasteful (over time) to do a complete fluid exchange of the transmission using the cooler return line, rather than one or more drain & fills. Here are instructions on how to perform a cooler line exchange: You will need: 12 to 15 quarts of automatic transmission fluid A clear gallon jug, something like an empty milk jug Another large container to store used fluid for disposal 1. Disconnect the transmission cooler return line and secure it in a collection bucket such as a clear gallon milk jug. This will be the hose on the passenger side of the vehicle; disconnect the end leading towards the transmission. 2. Have a helper start the car while you watch the bucket - once it's half full (2 quarts), yell for the helper to stop the engine. 3. Add 2 quarts of ATF through the transmission dipstick. 4. Drain collection jug into larger jug (i.e. a Disposoil - these only hold 10 quarts though in my experience, so have something else to hold the last 5 quarts). 5. Repeat steps 2-4 until you're out of ATF. 6. Check fluid for proper level (see the next question and answer for details), and recycle the old ATF. Any place that takes used oil will likely recycle ATF. I'd also strongly consider installing a Magnefine in-line filter. The Magnefine contains a very strong magnet to catch all ferrous wear material, and filtering media in the range of 35 microns to catch anything non-ferrous. A 3/8" Magnefine will fit the OEM transmission cooler hose. See a Magnefine filter in use for 23,000 miles opened here.

Sorry to hear about your engine failure. You're the third person to report power valve screw issues in the past two months or so. It's a shame that Nissan doesn't recognize this as their manufacturing defect and perform a recall.

I get 17MPG with 100% city driving with my 2WD, those with 4WD get 15-16 around town I think. 9.3 MPG is pathetic. Stick with 91 octane, it's ethanol free as you say and the engine prefers 91+ octane anyway. Make sure your SES bulb isn't burnt out. Engage the parking brake and set ignition to "ON" and make sure the bulb lights up.

Yeah, that's the cheap way of doing it. I'm not sure whether it'll stand the test of time, it might be worth it to get something beefier and built purposely to act as a PCV catch can.

A catch can is a device that is installed in-line on the hose leading from the PCV hose to the intake manifold. The blow-by vapors slow down and condense in the container and eventually must be dumped when the catch can becomes full, which is the only downside to a PCV catch can set up (constant maintenance). Some people use an in-line air tool filter. NICOclub has a DIY guide for installing a catch can on a Maxima, but the basic concept is the same for almost every vehicle with PCV. See the guide here.

What's the idea behind deleting the EGR valve? Exhaust gas recirculation theoretically increases the efficiency of the engine, read here.

Mine is secured by security Torx screws. It is also simple to remove, no prying required.

I was able to see the holes without taking off the engine cover. Perhaps you were looking in the wrong place.

If you install a PCV catch can, it will condense the oil vapors that come out of the PCV valve and eliminate a lot of oily build up in the intake manifold. But the build up in your pic looks pretty nasty, not sure what to make of that.

Yes, that is the correct procedure. It's also a good idea to clean the throttle body, yes. I think you might be changing the air filter too often. All filters get more efficient as they load up with contaminants, so changing your air filter so frequently might be allowing more contaminants through, as well as any contamination that might result from the act of changing the air filter (i.e. dust or sand falling into the airbox, etc). Just because the air filter looks dirty doesn't mean it's not working. You might benefit from an air filter restriction gauge to tell you when it's time to replace it.

There is nothing missing, the replies that make no sense are just people joking around. These screw holes can be used as a ground, but there is nothing there from the factory.

Yep, that's fine. I've used it before without issue.

I pulled the info I quoted (60mph, 500 miles) out of my 2001 owner's manual. Thanks for the correction.

I also doubt that the cooler clogging is as common as some make it out to be - more info in this thread - but it seems possible and is something simple to rule out, to begin with. If the cooler managed to get completely clogged with debris, I'd have expected noticeable issues prior to a sudden failure.

The severe service interval for ATF is actually 30k; the interval for differentials is 15k. Yes, nismothunder's suggestion is to eliminate the cooler out of the circuit and just use a U-shaped section of hose to connect the cooler inlet & outlets. The owner's manual specifically states: Speed in this case being 60mph, and distance less than 500 miles. I think it would be wise to do a pan drop and filter change, it's possible that the strainer has clogged as well.

Yep, that would be cylinder 1. Bank 1. What's wrong with your current MAF that prompted you to try a Maxima MAF? Strange that you've having issues with one. You purchased this MAF?

The MAF is held on by 2 tamper-resistant T20 Torx screws. Disconnect the battery, then disconnect the MAF's wiring harness, then remove the screws and the MAF will come out. Spray the MAF's wire like so using a MAF sensor cleaner:

Misfiring dumps excessive raw fuel into the cat and definitely does harm by reducing its reactive surface area. Which cylinder was misfiring?

The lines are easily accessible, they're right at the bottom of the radiator. You won't lose much fluid from disconnecting the lines, and you'll lose even less if you pinch the lines.

Yeah, if you don't burn any oil and never had a misfire condition for a significant number of miles your cats are most likely fine. Mine are fine at 131k.

Before replacing anything or adding an auxiliary trans cooler I'd do what nismothunder said and bypass the stock cooler with a section of additional hose to see if that alleviates the issue.

What makes you think the cats are shot? Does your engine burn a ton of oil?