jux

I have a 99.5 pathy with 220K miles on it, original owner. A while ago the CEL light came on and I wasn't up for an emissions check so let it go. Have to fix it now and the codes were P0138, P0325 and P0505. Fixed the P0138 (o2 sensor), ignored the P0325 and started working on the P0505. P0505 indicated IACV even though I was having no idle issues and it was idling well at 750 RPM. First step I took was to remove and check the IACV just in case. Got to the the IACV after much cussing and decided to just replace it. The IACV that came out checked out fine but I really don't want to have to remove the Plenum with all the blind connectors and hoses. Put the system back together and now it's running horribly. The IACV valve is clicking multiple times per second and the idle is bouncing between 900/1200 after it warms up feeling like it wants to stall. Not sure where to look for the issue. I can't find any unconnected vacuum hoses and the electrical connections seem tight. I don't think there is an idle relearn procedure for the 99.5 but maybe I'm wrong. Any thoughts are appreciated.

No problem, I know it frustrates me when people don't post the end of the story when it would have been really helpful. If I knew then what I know now I would have gone to the valve cover gaskets first based on the observation of oil on the side of the bellhousing where the dust cover meets the bellhousing. At the time I thought that the oil was getting through the dust cover but after seeing how the tightly the dust cover is bolted to the bell housing I don't think I would have seen oil on the side of the bell housing if it was coming from inside the bell housing.

For historical purposes I'm going to finish off this story. Initial problem was an oil leak at the bottom of the transmission bell housing. There was oil elsewhere on the engine but after 200k miles that didn't surprise me. Talked it over with some friends and came to the conclusion it was the rear main oil seal. To replace the RMOS I had to drop the transmission. I followed the Haynes manual and used the service manual to get an idea where some of the parts were because some of them I had to go in blind. I was going to try and list the steps but there were too many. Some notes I can offer from this operation are as follows: 1.) I needed two universal joints on a socket to get to the crankshaft sensor on top of the bell housing. It's a blind bolt so it's hard to get to but was easy to put back in. 2.) I had to order the copper crush washers for the transmission line from Nissan, it didn't seem like anyone else had them. 3.) If you are removing the transmission entirely from under the truck take into account the height of the jack when you decide the height you will jack up the truck. Luckily I didn't need to take it out from under the car but the 10 inches I had the truck jacked up was not enough if I wanted to move the transmission from under the truck when using this adapter transmission adapter. 4.) The transmission fill tube is about a half inch too long to remove from the truck when the transmission is on the truck. You have to remove the transmission to remove the transmission fill tube. Conversely when putting the transmission back on make sure to insert the fill tube as you're raising the jack into position. 5.) Two people would be really helpful when lining up the transmission for re-installation. 6.) Do not use water based paint when marking the relative positions of the drive shaft and the drive plate to torque converter. I did and after a few weeks of condensation it was almost entirely gone. 7.) To remove the top bolts on the transmission you have to lower it, use a deep socket on an extension and a universal joint to reach the bolt. 8.) The passenger side upper bell housing bolt has an air line right in front of it. You can get around it, don't work about breaking anything because the bracket that holds the air line in place is held in place by the same bolt you're removing. The whole thing will just fall out once you remove the bolt. The air line is just coming from the back of the transmission and ends about where that bolt is. The end of it just hangs in space. 9.) For putting the bolts back in on top of the bell housing I couldn't get my hand to hold on to the bolt at the same time I was trying to get the socket in place, there was not enough room. I put gasket sealant in the socket, put the bolt in the socket and then waited about 30 minutes to let it set. I was then able to just use the socket with the bolt in it to get it into place and screw it in halfway. the gasket material easily let go when I pulled the socket back out. 10.) The Haynes manual recommended 9 quarts of transmission fluid, the service manual says 7.5, the service manual is right. I took the car to the shop after the job was complete to have them look at that rattling I described in a previous post, it turned out it wasn't the transmission at all but the heat cover over the catalytic converter. Not the first time I have been fooled by that tin. And after all of that, the oil leak wasn't from the rear main seal. The oil leak was from the valve cover gaskets leaking down the back of the engine making it look like it was coming from the transmission bell housing. Replacing the valve cover gaskets was a much easier job. Neither the Haynes manual nor the service manual do a good job describing how to remove the upper air intake manifold though.

So I have run into an issue. Got the whole thing apart, put the whole thing back together and everything seems to be ok except at high RPM when changing gears I'm getting a loud knock from the transmission like a loose exhaust heat shield but I know that's not it. As part of the procedure I replaced the fluid and the filter and all of that seems ok, level is fine. Any thoughts? Thanks. Edit: I should mention that it happens in park as well.

That did it! Lowered the tranny about 6 inches and was able to snake a long extension with a U-Joint and 9/16 deep socket to get that bolt. Next weekend get to test my mettle at getting everything back together. Thanks for the help.

Through the shifter is a brilliant idea, I would guess it would have made getting to the crankshaft position sensor a little easier as well. I read about leaning the engine and tranny back a bit to get to the bolts but am worried about what that's going to do to the engine mounts. How much of a tilt would be too much?

Pezzy: Thanks for the welcome. Precise: Thanks for the service manual pointer. I think I should install a computer in my garage so I can refer to it Off: I'm just North of where you were in AA County, spent a lot of time in PG in my youth. Coincidentally Most of my extended family is around Painesville so I wind up around Cleveland a lot. My daughter loves the science center on the lake.

Original owner of a 99.5 SE Pathfinder. She's got over 200k on her now so she spends more time in my garage getting the maintenance done than she used to. Mainly my wife's car but I can see a short ways down the road where it's going to belong to a teenager. I'm a home mechanic and do most of my own car work between a 96 Civic (250k), 92 F-150 (150k) and the Pathfinder. I consider myself handy enough to have so far avoided breaking anything major on any of the cars (to be edited later) during the repairs. I don't do mods to the cars because I don't off-road nor need anything more than the transportation they provide. I joined the forum to get differing opinions on how to approach various repair issues. I am a software/electrical engineer so if there's anything I can offer in the way of knowledge trade I would be pleased to provide what I can. I also have a good bit of knowledge about home repair and some knowledge of powerboats. Obviously anything I can gleam from my repair adventures is also something I will share constantly.

I'm replacing the rear main oil seal on my 3.3L V6 99.5 SE and have everything off according to the service manual and Chiltons manual except for the rear crossmember holding the back of the transmission and the bolts holding the transmission to the engine. My issue is that I can't see the top passenger side bolt holding the transmission to the engine even using mirrors. It appears that the rear brake lines are routed in front of it or are obscuring it. Is there a trick to getting to this bolt? Thanks in advance For full disclosure I have asked this question in 2 other forums but have not received a reply, sorry for cross posting.