PCV valve replacement - a horror story

[Towncivilian]

So, today I replaced my PCV valve. It took 7 hours. Here's why:

 

I obtained the four gaskets for the upper and lower intake manifolds, the PCV valve itself, and the grommet that goes around the PCV valve a few days ago. Today, a friend and I started work on it at about 1 PM. It was raining, so we moved some crap around in his garage and I pulled the front end of the PF in. This gave us very little room to work in. So anyway, I remove the plastic engine cover and start work on the passenger side, by removing the two brackets that hold up some wiring harnesses. That took all of 2 minutes. I then began removing the various hardware atop the upper intake manifold - accelerator bracket, etc. I'm short, so I had to climb in and crouch atop the top radiator support to gain access to some bolts... this becomes a recurring theme.

 

With that stuff off, it's time to remove the air intake tube and throttle body. To further complicate things, there's a bunch of immovable stuff up pretty much everywhere in the garage, so to access the driver's side, I had to go through a labyrinth involving walking over and around stuff constantly. My tools were also on this side, so this got tiring quickly. The air intake tube and throttle body came off easy, as does the upper intake manifold. Bolts/nuts get labelled with masking tape and a sharpie.

 

Now the real problems start. As some of you know, the lower intake manifold collector has a support bracket on the passenger side corner, right up against the firewall. It's impossible to get tools back here pretty much. The uppermost bolt came out pretty easy; the other, not so much. For some reason, both were already pretty loose (a blessing or a curse?). It took 30 minutes fiddling with a box wrench, sockets, etc to loosen the bolt enough to spin it out by hand. Why is this thing back here?! The top 2 bolts and 2 nuts on the manifold are then removed.

 

So at this point, I'm drenched with sweat since it's over 9000 degrees out. It stopped raining, so it's ridiculously humid. Sweat doesn't help. We lift the lower intake manifold off, and what do we find? A PCV valve snapped in half. I forgot to move the PCV hose aside, and the undue stress caused it to snap.

 

It took probably 30 minutes with some pliers to actually pull the remaining half of the valve that was still inside the valve cover, since a good majority of it fell in the damn valve cover. After carefully applying pliers to remove the largest chunks, I, uh... felt around with my index finger to retrieve any remaining significant chunks of residue. Not fun, let me tell you. At least I didn't need to pull a valve cover.

 

So, now that that's over, we wrestle with the new PCV valve and grommet for 10 minutes trying to fit it in... the grommet and valve are a very tight squeeze. We eventually get it in, I slap the new gasket on, and we take a well deserved break.

 

We spend an hour trying to reposition the lower intake manifold back on the engine, which was a troublesome task due to the cramped engine bay, cramped working area, and the extremely stiff PCV hose that needed to go on before the manifold could be set in place. We call a buddy over and he helps us, and we finally maneuver the thing back on and I start buttoning things up - ensuring to use the proper torque spec and tightening order, mind you. The damn support bracket bolts were not torqued with a wrench; the easier-to-access one was tightened with a box wrench, and the other one was just as snug as I could get with my fingers.

 

I complete reassembling the manifolds. I loosely install the throttle body, then realize I still don't have the proper hex bit to torque it to spec. I removed it using an 8mm Allen key, but my 154-piece Craftsman toolset doesn't have an 8mm hex bit. Oh well, tightened using the Allen key in the proper tightening order, hope it'll be fine.

 

More annoyance strikes during reinstalling the intake tube. The stiff vacuum hose on the firewall side gives us trouble, but by this point we already had installed and tightened the damn tube (d'oh). We remove it, and wrestle with it some more... we're done, right? I check over hoses, etc and start it up. We hear a high pitched noise, and I shut it off. The damn air intake tube wasn't flush at all with the airbox housing (hey, it's dark, and we're sweaty and tired by now). We remove the thing again and put it on properly this time, and all is well.

 

But wait, there's more! I ended up with an extra part: one spacer. No idea where it came from. It was resting on top of the rearmost wiring harness support bracket on the passenger side (the one with the stud for the engine cover), but it obviously shouldn't have been there since the nut for the engine cover couldn't be screwed on with it there...

 

Whoever buried the PCV valve under the intake manifolds should be shot. I sure as hell hope I don't need to do this again any time soon. And I thought putting threadlocker on the power valves was tough... hah. They all look fine, by the way.

 

I think this is my longest post on NPORA. And I bet I'm the only one who fingered their Pathfinder. I need some :coffee!:

[carwilef7]

At least you had a workout. Took months for me to figure out that the coolant temp sensor was behind an occasional flooding issue. So what do I do? Buy the sensor and torque it in to the point that it breaks in half because I'm trying to make the harness line up - DOH! $30 dollar part cost $60 because of my own stupidity.

[01silvapathy]

Wish you had done a write up

[xplitive]

I was looking at replacing the pcv to see if it would help my oil consumption but decided 1 qt ever 1500 miles looks normal, even for those that replaced their pcv's. Most folks just replaced the entire valve cover but I never knew why.. thinking your experience must be the reason - ouch!

[Towncivilian]

Wish you had done a write up

 

Follow this guide.

 

 

I was looking at replacing the pcv to see if it would help my oil consumption but decided 1 qt ever 1500 miles looks normal, even for those that replaced their pcv's. Most folks just replaced the entire valve cover but I never knew why.. thinking your experience must be the reason - ouch!

 

My experience was caused by my mistakes alone - poor work area, forgetting to disconnect the most important hose of this job, running out of intake cleaner halfway through (I was a bit overzealous with cleaning the UIM)... this would have been a 3 hour job otherwise, I think.

[Towncivilian]

Here is the parts list for replacing the PCV valve for a 2001 or 2001.5 Pathfinder:

• 16175-4W000 GASKET-THR (throttle body gasket)
  
• 14033-4W000 GASKET-MAN (first of two upper intake manifold gaskets)
  
• 14033-4W010 GASKET-MAN (second of two upper intake manifold gaskets)
  
• 14032-4W00A GASKET-ADA (gasket between upper and lower intake manifolds)
  
• 11810-31U00 VALVE ASSY (nonthreaded PCV valve)
  
• 11812-41B00 INSULATOR- (grommet that goes around PCV valve)

All of these parts are required. I paid $69.82 after tax at my local dealership (I get net/wholesale prices).

 

For 2002-2004 R50s, I believe the PCV valve is threaded, so it will have a different part number. I do not know if the grommet/insulator is required since it's a threaded PCV.