WAPathy

Hey all, I replaced my PCV valve in my 03 Pathfinder while I was locktite-ing the power valve screws. I ordered a PCV valve (AC Delco CV941C) prior to beginning the procedure, but found that it was not the same as what was in the engine. The threads and overall dimensions were different than the original part. This lead to a trip to the local parts store. Their computers showed yet another variety of PCV valve that was not like what was originally in the engine. They recommended a model that did not have threads (FRAM FV373). The PCV valve that I eventually used was a Airtex 6P1238, which has threads that on the valve cover side. My Pathfinder has 75k miles on it. I bought it when it had 22k and suspect that this is the first time the PCV valve has been replaced. Long story short... does anyone know why there appears to be different PCV valves for the same VQ35DE engine? Has the design of the PCV valve changed over the life of that engine? Secondary question, I read somewhere to replace PCV valves every 30k-50k miles. Does this seem like a reasonable interval? Thanks! Bryan

1) Mine were definitely tight - they did feel like they cracked lose. (I slightly stripped the first screw when backing it out because I assumed it would be loose and didn't apply enough pressure. The others did not strip as I applied more force on the screwdriver to loosen them.) 2) Yes, I believe the '03s have a drive by wire system, although I guess I assumed all the R50's with the VQ35DE had electronic throttle control. The throttle is fairly touchy such that when I first had the PF, I often started a little quicker than I would have liked. As with all things like this, you get used to how much pressure is required. 3) I'll post to the wider community and see if anyone has some ideas. Thanks again, Bryan

Thanks! I'm in Mill Creek.

Just wanted to say hi from Seattle, WA. This is a great forum! I have a 2003 Pathfinder R50 4x4 with an automatic transmission. It does not have the LSD. I followed the how-to's on repairing the power valve screws on the VQ35DE. (No issues were found). The forum was extremely helpful solving this issue. I also recently replaced my stock resonators with an aftermarket variety. The originals were leaking out of the side seams, making the vehicle sound rough. Thanks for creating and maintaining a great site! Bryan

Hey Bowtied, Just wanted to offer my thanks on an excellent guide. I wouldn't have attempted this fix without your guide. Couple of comments (I have an '03 SE Auto 4x4 with 75k miles): 1) My power valve screws were in tight and also had some gunk on them that we cleaned out prior to adding locktite. Not sure if they had been threadlocked or not at the factory, but they were not backed out of the valves at all. 2) My throttle body looks different than the one in your pics. On the backside of the throttle body (firewall side), there is what appears to be an electronic control module and there is no linkage on the frontside. Any idea what changes occurred between the '02 and '03? 3) I replaced my PCV valve while I had the manifolds off. The PCV valve in my engine (probably OEM) is threaded into the valve cover. If you search on rockauto.com (or another parts website), two types of PCV valves come up. One, the Fram version, just seems to plug in and is not threaded. This part did not look like the one that came out of my engine. The second type is threaded and costs 3-4x as much. However, there seem to be different versions of threaded PCV valve. The ACDelco variety does not fit. Any idea why different valves are showing up for the same engine? Again, thanks for a great post.