When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Step # 27 for removing the "Secondary Bulkhead Center Panel" (aka "Plastic False Bulkhead") shows 5 black arrows pointing to the front and 2 appear to be pointing to the back of the engine harness cover. I assume that means that there are 7 fastenings. The diagram shows cover to be one-piece.
The panel on my car is in two pieces the division being vertical & roughly in the center. Also, I don't think the number of fasters is as many as shown.
I have the panel sufficiently loosened so that it moves up and down at the top and seems that it is close to coming out. The resistance is at the bottom & because of the insulation, I can't see the other fasteners. Seems that I could get to it better if the air intake was removed.
Question: At what point should I endeavor to remove the air intake manifold. From some of the photos Pete & Thomas have sent, it appears that they have taken the air intake manifold elbow off by now. So, to restate and simplify the question: What do I have to remove to get to all the fasteners & fittings to remove the air intake...? Seems like the two large bundles of wires will have to get out of the way?
Are you talking about the whole intake manifold, or just the airbox in front of the throttle body? Since you point out that the firewall trim is in the way, I assume you mean the manifold.
The coolant hoses that attach around the throttle body need to be detached, and the brake booster vacuum hose needs to be disconnected. Those coolant hoses include small hoses to the EGR valve, and the hose that disappears under the intake. A vacuum hose on the back if the throttle body, and where it attaches to the fuel pressure sensor at the front of the right-side fuel rail. The throttle body can stay on the manifold, there are about 47 electrical connectors that you can reach, and two that you can't. the harness are attached to flat rails, one on each side, that simply unbolt. Disconnect the ones that you can reach, move the harnesses out of the way, then remove the bolts attaching the manifold to the heads, and move the manifold forward far enough that you can now reach the two connectors on the back, then you can lift the manifold out.
I did not separate the lowers from the upper, but lots of folks have said that the gaskets there were bad for them and causing intake leaks. For the new gaskets against the head, make sure you get the metal ones that have the clips that fold up to hold them in place during reinstallation. The first couple of gasket sets I ordered showed the metal gaskets in the picture but I receive cheap paper gaskets, which you cannot keep in place during installation of the manifold.
Last edited by wfooshee; Mar 26, 2024 at 09:09 AM.
Thank you for sharing your invaluable experience-based knowledge!!
Sounds like the heavy lifting is about to begin! I've gotten the brake booster vacuum hose removed!
The gasket advice is particularly helpful. I struggled mightely with the oil pan gasket & in spite of it all, there is still a slight leak! & on a relative basis, that gasket was a piece of cake! Now, I see why so many have kindly wished me "good luck"!
Since you didn't mention the plastic bulkhead, I'm curious -- did you omit it assuming it had already been removed, or is it not a prerequisite? I'm hoping the latter.
Hope to get back to it in earnest after Easter. Have a good one, Steve
My ultimate goal is to replace all of the hoses that I can, including the valley hose that is leaking. Hence, the need to remove the SC.
I assume the firewall has the silver insulation coating. It is behind the engine & attached to the cabin wall. It is good if that doesn't have to be removed. But, somehow, I thought that it had to be.
In the picture below, what would appear to be the top of the firewall, is actually 2 separate pieces meeting with a slight overlap in the middle & it may be called the "engine harness cover". On the passenger side of my LH Drive xjr, the 2 heater hoses I'm taking off pass through this "cover" right up against the bulkhead. So, I take it that the "engine harness cover" at least on the passenger side, has to be removed? This piece is seen in the photo right in front of the large bolts for the struts that have been removed. You can see where the two halves come together in the middle. It seems like this has to be removed to have more room to get at the other stuff in order to remove the intake manifold. I have it (the cover) loose at the top & you can see that the brown insulation on its front is loose. I don't see where to loosen it at the bottom in order to remove it. If the intake manifold weren't there, I think I could get my hands down to where the fasters for the "cover" must be. Any thoughts? Thanks, Steve
Regarding the center bulkhead, contrary to Wfooshees statement, I would definitely remove it, as it makes things so much easier in the long run. The space at the rear of the engine is so tight that every inch counts.
And yes, the center bulkhead comprises of two pieces.
I hope that the pictures give an idea of how much of a difference the removal of the center bulkhead makes.
It appears that you had to tear the brown top insulation? I think it is the same piece that also runs lower. The lower part has a foil-like covering? But is the plastic part at the top separate from the bottom; perhaps divided where the foil-like insulation starts? Or, is it 2 large panels, overlapping in the center?
I tried to remove the insulation without destroying it, and managed for the most part. I then glued it back afterwards (I think that I used double sided tape).
I found another picture, it should help to see how far down the part reaches:
Best regards,
Thomas
Wonderful! So, the top plastic doesn't connect with the plastic with the foil-like part! On mine, I believe the insulation from top to bottom is all one piece with the lower coated with the foil.
That what you said "goes out the window" is horsefeathers! Your comments about the wiring, tools, getting hoses off, etc. have been very helpful! I am finding that having the 4 different engines in the 350 creates untold confusion!
I very much appreciate your help, not just in this instance, but throught the years! I wonder if the powers that be on this forum have considered having a division of the 350 based on engine work. All other stuff, like body work, could remain amalgamated?
I think that unfortunately it is not as simple as that.
You have 5 different engines (3.0 V6 petrol, 2.7 V6 Diesel, and 3 V8 engines: 3,5, 4.2 n/A and 4.2 supercharged. And you have the 4.2 supercharged engine with VVT (from MY2006 onwards), and without, so maybe it is even 6 different ones...
Then you have 3 different body styles (you might contest this), although the differences between x350 and the sometimes so called X356 were not big, but the changes to the X358 were major at the front and back.
Although the X356 (it was introduced in MY2006) looks pretty similar to the X350, there were major changes to the electrics, a completely new braking system, the aforementioned introduction of VVT on the 4.2 supercharged, tire pressure monitoring system, and other changes.
The X358 not only features the different styling, it comes with further additions like the ventilated seats.
This Is How It Is Done; Thanks to All For The Help!
As you see in the photo, the piece divides down the middle. The instructions in the manual show it as one piece.
After removing the brake vacuum hose and the two heater hoses, you don't need to take anything else off to remove this upper plastic whatever-the-hell-it-is-called. No need to touch any airconditioning parts, etc.
You can remove all the star washers, etc. holding the plastic pieces in place without removing the non-foil insulation. However, it must be torn out in order to remove the last two fasteners - one low on each piece. I will try to find a susbstitute for it when I put it back; hope I'm not being presumptuous.
Thanks again & best,
Steve S.
Thanks to everyone contributing to my success with this step.
Engine Harness Cover
