August59

It is the A.I.V system. There's a reed valve and an air filter inside. These filters tend to be out of sight and out of mind so they're not changed routinely as they should. They can become clogged (probably mostly from just rotting over time). I would imagine at some point they may cause some problems. I can could send you the pages from the FSM, but you may have to PM me and send me a email as I don't think we can "paste" them on the forum.

Been thinking about that since we don't have emissions. I would have to cap where the lower end of the pipe connected? And, the vacuum port on the solenoid?

Nice video!

Thanks. Been soaking it with PB Blaster for the last 3 or 4 days. Probably try to get on it this weekend.

Planning to pull intake plenum. Seems like the only way to clean out the EGR/tube completely. The tube to throttle body isn't blocked, but I would say it 3/4 open as there is a carbon ring around the inside of the tube. If I could clean it without removing plenum I would - Taking suggestions?? Any words of wisdom on removing a heavily rusted EGR and pipe would be greatly appreciated as well? If I have to pull plenum should I replace the thick washers (dealer calls them a spring/heater??) on the studs? I've already changed one of the rubber hose that's under the plenum. Have no idea if there are more??? Thanks ahead for any advice!

I replaced mine with WARN years ago, but there wasn't anything wrong with the automatic ones. Anyway I still have the original ones for back up. The manual ones have worked great and the best I can remember it all the parts on the lock out were replaced when I put new ones on, so there was nothing to trash. That was 20 years ago though, but I hope this answers your question.

I found one picture of the TB apart and it appears that there,isn't a lot going on parts/piece wise in it. Since it's fuel injection it looks like the TB is not much more than a vessel to hold the injectors in the right place and something to attach all the sensors/solenoids to. Biggest thing seems to making sure not to damage the injectors when removing. Since the right tool is supplied with the rebuild kit that should be problem. We're going to give it a shot. And I'll guess I'll go ahead and pull the plenum and replace the coolant hoses under it and clean the EGR and tube out. My fear there is removing EGR and the pipe attached to the EGR since it appears to have a thick covering of rust

I have the Throttle Body off, but wasn't quite sure what to expect if I pulled the upper half apart from the bottom half? I know caution has to be taken removing the injectors and the need for the correct tool, but that tool is supplied in the rebuild kit. Just hope parts don't start falling out that I can't figure out where they go?!?! Thanks

Shout out! - Even though the thread is a little old. There have been quite few occasions where cleaning the terminal for the Cylinder Head Temperature Sensor (CHTS-add to acronym list?! - based on 89 VG30i FSM and I do have a copy if anyone needs it) was a logical step in diagnosing problems. Well all I can say is I have clean terminals/connector on my Water Temperature Sensor (Sending Unit for gauge). Just got didn't read the FSM thorough enough and at the time wasn't able to find a clear picture possibly. Thank's to all that cleared the fact up that I had been looking at the wrong thing for a few years!

This is the only place I've found the ones for my 87 Pathfinder, but they sure think a lot of them. https://parts.nissanusa.com/nissanparts/index.cfm?action=replacement&groupid=A&sectionid=118&jointvehid=8192&siteid=14

Not planning on pulling plenum, if I can possibly help it. The EGR tube from TB to EGR is what 3/8" (?) dia. and it has a carbon ring about 1/8" thick around the tube or it's approx. 2/3 open. I would like to clean it out, but I'm pushing my luck. If I do pull the plenum how hard is it to remove the EGR and the pipe. They're both rusted on with thick layer! I can see pulling the plenum to be the best way to clean it. Knuckleheads at Nissan weren't thinking when designed that setup!

I'm going through cleaning all connectors and sensors plus changing vacuum lines, coolant (including the ones on the throttle body) and fuel lines (under the hood). I have throttle body off of the intake and I was just going to clean it good and new gaskets at the intake. Throttle body hasn't ever been broken down and cleaned, but judging by all the black junk that rinsed out of old coolant lines and heavy carbon build up in the port on the bottom below MAF I'm considering buying a rebuild kit ($40 which is cheaper than the 2 intake gaskets from dealer) and tear it down and clean it good. The rebuild kit comes with all the gaskets plus solenoid o-rings and even a punch to remove the injectors, but this is where I'm pondering just leaving the injectors alone or removing them and replacing o-rings/seals plus cleaning them. Keep in mind that the Path wasn't running well before I started down this road and what I believe lead to the poor performance was a coolant line (I hope there is only one???) under the intake had started leaking and it ran hot, but I shut it down almost immediately and I was close to home. However, the coolant soaked the right side of engine including the throttle body (ex: TPS terminals and connector had a lot of corrosion build up when I checked them, so I'm guessing the coolant was able to get i there at some point) and the Path ran fine for a few weeks, but went into a steady decline and it's been parked for awhile. Should I break this TB down and clean it good including replacing seals/o-rings for injectors? Anyone had a bad experience with these rebuild kits? I'm looking at the one from "Rock Auto" https://www.rockauto.com/en/moreinfo.php?pk=46927&cc=1211768&jsn=377 Thanks ahead for any feedback.

The pipe from the throttle body to the EGR has some carbon, but it's not close to being "clogged". With the throttle body off can the EGR be cleaned or would it be better to leave it alone as long as it's operating fine?

Just wondering if anyone had any good ideas as to how they went about replacing hoses that appear to have been long discontinued? Ex; PCV hose from valve cover. ID dia. on each end is different as well the hose from other valve cover to air breather has different id dia. ends Unless anyone still knows of a source for these because I'm batting zero. In past I've went with smaller diameter hose and use heat gun to stretch the small end. This works, but it thins and stresses the hose pretty be, but it was cheap hose may try again with higher quality if possible. Any problems using standard dimension hoses as opposed to metric dimension hose as long as they are a very close match? Thanks ahead of time for any feedback

That might get it. I had an old set of welding tip cleaners which I thought might work, but haven't seen them in awhile.