Boys and Girls,

I currently have the upper intake plenum removed on my '02 V6, taking care of a P301 fault. Hopefully it's just the coil, with a new one in hand ready to install. I've also got to replace a valve cover gasket due to an oil leak. I got to wondering about the infamous elbow below the lower intake manifold. From what I understand, when this elbow fails, you can expect to get P0171 and P0174 codes for a vacuum leak.

Was there ever a campaign or recall to upgrade this elbow? I'm wondering if I have to keep digging to replace it. I see lots of fragile little connectors and hoses just waiting to break. I've already had two exterior vacuum lines break (easily accessible, phew!), and would prefer not to cause any more damage.

I'm thinking of doing a smoke test of the line. No codes other than the new P0301, and fuel trims have been looking good. Or is it false economy to hope the existing elbow will remain serviceable for a long time? The car has about 375K miles, so is no spring chicken. Part of me is thinking if the elbow was going to fail, it would have happened by now. It would be easier to convince myself if I knew there had been a campaign to install a more durable elbow, although I'd have no easy means to know if my car had it.

If a preemptive replacement is advisable, any tips to make it easier? I've seen two guides, and both mention it's very difficult to install the new elbow:

jaghelp.com: Intake manifold in a 2002 S-type 3.0L

JagRepair.com - Jaguar Repair Information Resource


This picture shows the location, with the suspect rubber elbow (in the large red circle) immediately aft of the oil separator. The image makes it look like a 45 degree elbow, but it's really 90:

http://www.jagrepair.com/images/PDFD...r%20System.pdf

What about the rigid elbow aft of the rubber elbow, underneath the PCV valve? How difficult is it to remove that? Seems that would make installing the rubber elbow a lot easier.

 

Hi Karl,
Not long ago I have been digging around that area in my 04 S-Type. I can't remember having seen such an elbow or any of those parts it connects to. Is it possible I don't have that at all? In that thread of mine, somewhere in the middle is a picture of that same area on my S-Type:

https://www.jaguarforums.com/forum/s...aks%94-263540/

And you mentioned an oil leak on the cam cover...: Are your cam covers still in one piece, of have your (like mine) self-destructed due to galvanic corrosion (the cam covers are magnesium)?

 

It wouldn't be a recall.

Yes the elbow is a common fail on the VIN <M45255 cars.

 

Peter your 2004 my does not have the infamous valley rubber elbow.

Karl, going through the hassle of pulling plenum already. I would replace the elbow, both sets of the intake seals and both cam cover seals. That way you will never have to deal with those parts again.

Hey congrats on the 375k!!! I just turned 330k on my daily, 2005 Cadillac Esclade.

 

I totally agree. A stitch in time…

 

Well, you pre-emptive replacement guys are zero help. Whatever happened to telling somebody what they wanted to hear? Criminy...

FWIW, I gave the system a good smoke test last night. Zero leakage from the hose and the rest of the valley area. I also got in there with an inspection mirror and found absolutely no sign of deterioration. Both of the VVT solenoid grommets are leaking like crazy, so those are on order and should be here tomorrow. I was thinking they were included with the valve cover gasket set, but no dice. Wish I had noticed that earlier.

Got to looking at the metal elbow aft of the infamous rubber elbow. Here's a view of one, shamelessly stolen from eBay:



The troublesome rubber elbow is to the right of the picture. The left of the picture is the part that points straight up. Note the bolt hole in the bracket. You'd be working by Braille, but there's a stud and nut on the back of the cylinder head. With a short ratchet, undo the nut and you could reposition the whole thing to make it easier to install the new rubber elbow. I think that would be a lot easier than trying to fight a new rubber elbow into place between two fixed tubes.

One little tip to pass along. Across the back of the engine is a black plastic shroud for the wiring harness. It attaches via the two aft bolts on each valve cover. Years ago, I replaced the gasket on the easy side, but remember fighting that thingamajiggy. If you remove all four fasteners, you can get it further out of the way. The harness also runs forward along each valve cover, so undo those brackets to let the whole shooting match slide aft. The harness was pretty tight, so there was no room to move it until completely loose. Not a big deal as those fasteners have to come out anyway to remove the valve covers. But if only doing one side, you may need to undo the other side so the harness can move.

 

The cam covers are fine. The easy (visible) side is aluminum, or some similar durable alloy. No corrosion whatsoever. The difficult (hidden) side is some kind of plastic or composite. Apparently only the later models have the troublesome magnesium covers.

 

@kr98664, I find it's easier to install the end to the breather outlet by loosening the bolts so the pipe can be accessed. I also find spraying a small amount of silicone on the inside of the hose before pushing it onto the breather outlet pipe makes the reassembly easier. One note of caution is to make sure the paper gasket between the breather outlet and the engine block isn't torn or out of position if you choose to remove one of the bolts.

If you haven't done so already, replace the cooling system hoses and o-rings from the 'Y' pipe whilst the upper and lower inlet manifolds are removed.

 

On closer examination, the visible valve cover is also some kind of plastic or composite material. The outside is painted silver, that's all.

As always, this revelation is not to be construed as me being (W word), but simply less correct than usual.

 

Karl. That is a few more less corrects than usual as of late. Time to go camping maybe and recharge my friend

 

Yeah, you're right. I'm kinda out of sorts, off my game so to speak. Been through a rash of traumatic events lately:

1) Got a new smartphone. Accustomed to the layout and features of your old phone? Ha, let us change that for you.

2) Wife dragged me to IKEA. Spent the next few days assembling dorm-grade furniture. I think I'm suffering from particle board poisoning.

3) Wife rearranged kitchen with new IKEA stuff (see #2 above). So what if the coffee pot has been in the same place for 10 years and I could find it in the dark on autopilot...

What's next? Washing my bathrobe?

 

I understand the word ‘robe’, but what does that bit before it mean?

 

Some part numbers for anybody who wants to play along at home.


The elbow: Ford 3W4Z-6767-CA (Ford calls this a connector)

Between the lower intake manifold and cylinder heads: Fel-Pro MS96485 (set of 6)

Between the lower intake manifold and plenum: Fel-Pro MS96494 (set of 6, plus the 2 O-rings for the IMT valves)

Valve covers: Fel-Pro VS50610R (set of 2, plus seals for bolts and spark plug wells)

Gasket between throttle body and intake plenum: Fel-Pro 61351

Grommet between VVT actuator and valve cover: Jaguar AJ82577 (sold individually, 2 required)

There is a T-shaped plastic breather hose that connects both valve covers to the duct between the air filter and throttle body. Replacement may not be needed, but it's very fragile and may fall apart like mine did: Jaguar XR835745

Another fragile plastic tube runs aft from the throttle body. It connects to the elbow above the PCV valve near the back of the engine. Mine had succumbed to heat and age. With a tubing bender, I fabricated a replacement from 3/8” OD steel brake line. If you’d rather stay OEM: Jagua XR839225

 

Once your finished w/project you will be thankful for us in the peanut gallery.

 

Only thing to add to what Karl shared is the gaskets for the upper and lower inlet manifolds are VIN-specific.

 

A little update and a query...

Got the dead transmission issue going on, but hopefully that will be resolved soon ($$$). Initially the car ran great, but that was after reconnecting the battery, so the computer hadn't gone through its learning process. The more I drove it, the idle quality decreased. I was also getting a light chugging at low throttle settings, such as climbing a gentle grade at freeway speed. Adjusting the gas pedal a little bit in either direction seemed to clear that up. No codes, but my scanner only picks up OBD stuff, so it won't read any non-emissions faults. Fuel trims look great and I saw nothing out of whack with live data. I even tried getting the car to chug in hopes it would set a fault code, but nothing.

During the course of this recent work, I also replaced all 6 spark plugs and coils. I had lots of oil collected in the spark plug wells on both sides, so also replaced the valve cover gaskets on both sides. Two of the rigid lines in the crankcase breather system cracked and fell apart, so I fabricated replacements with metal tubing. I gave the breather system a good check with my smoke machine and saw no leaks.

I also replaced the O-rings for the two IMT valves. I previously had the upgraded green seals in there, but they were over ten years old. The new seals looked to be ordinary black O-rings, included with the Fel-Pro gasket set for the intake manifold.

Does it seem likely the new IMT valve seals could be causing this trouble? I've ordered a new set of genuine Jaguar green seals. The car is at the transmission shop now so it will be at least a week before I can install them. My current hunch is the IMT valve seals are causing a vacuum leak, but I don't really know for sure. I'd be very interested if anybody has experienced similar symptoms due to bad IMT valve seals. I'd even be okay if one of the new coils (Denso) had failed, but am not seeing any indication of that.

FWIW, when I killed the transmission, I had stomped on the throttle to watch for any errant parameters. Didn't see anything, but then again I was busy trying to coast to the side of the road...

 

If the fuel trims are not indicating a lean condition, the issue is most likely elsewhere rather tan the IMT o-rings.

 

This is NOT the preferred answer. I was thinking something more along the lines of "Brilliant troubleshooting, this should be an easy fix."

 

When you changed the plugs and coils, did you renew all 4 inlet manifold gaskets? Or just the top two?

 

Not sure I follow your question.

I count six oval gaskets between the lower manifold and the cylinder heads. You don't have to disassemble this area if only replacing plugs and coils. Then there are an additional six gaskets between the lower manifold and the big swoopy intake plenum.

Full disclosure: I decided not to tear down below the plenum. I was satisfied the infamous elbow was not leaking (smoke test passed with flying colors) and it showed no signs of deterioration. I only had the plenum and valve covers off. All new gaskets there. As previously mentioned, I also had the IMT valves out for new O-rings.