Hey Gang,
I had to have my transmission rebuilt a few weeks back and the engine had a misfire at idle/low RPM, which was causing the trans to shift weird so I had to take care of the miss. I replace the #2 coil and it helped a lot but the small miss was there and my OBD came up with multiple cylinder misses but no engine light. I took it to my local garage and they found an intake leak at the base of the intake (to the engine) replaced the gaskets and it still had a small miss/ leak and they are saying the upper intake is leaking and a new intake assembly needs replace because there are no gaskets for the upper part of the intake . The shop contacted a Jaguar dealer and were informed there are no gaskets for the upper part of the intake and the entire intake assembly needs replaced and that the intake is not serviceable. Any engine guru's out there maybe shed some light on this issue with the intake. The car is a 2004 S-Type 4.2 base model with 170,000mi. Still runs like a scalded dog. I found a used intake at Jag Bits but that was about it. Any enlightenment is greatly appreciated. Thanks

 

Might look at this thread?
4.2L NA Intake Gaskets
Can you post a picture of what your looking for?

Here is what JPART shows;



What number are you looking for?
#2,3 and 4 are listed as gaskets.
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@Cobbler, two questions come to mind:

1. How did the repair shop diagnose the air/vacuum leak(s)?
2. Have the cam cover gaskets been replaced?

 

I’ll find out tomorrow how he diagnosed it. At the time I posted this the tech was out of the shop. What should I expect from the test?

The cam cover gaskets have not been replaced. Should that be done?

 

Hello,
what does the workshop think? The intake tract from the throttle valve to the intake manifold?
How much does the complete intake tract cost? It may also be worth making a gasket yourself (or having one made). Does the used car have a functioning gasket?
Greetings, Willi

 

Thanks for the reply Willi. The intake gaskets in question are the eight rubber gaskets that go between the polymer plenum and the aluminum intake risers that bolt to the engine.
I found a complete used intake assembly for $186 and change on eBay. I also found the (8) rubber gaskets on Jagbits but the set of (8) are $190. https://www.jagbits.com/ssearch.html...old+gasket+kit. Really, the individual gaskets would be the better choice since know they would be new. Someone here posted about a set for a Range/Land Rover being the same so I'm pursuing that too.

 

@clubairth1 has already described a solution/idea above

Greetings, Willi

 

I'm curious if they performed a smoke test to determine exactly where the leak is coming from rather than start replacing parts. Also did they check the LTFTs and STFTs per bank?

Given the age of the vehicle, the cam cover gaskets and spark plug seals should be replaced to eliminate the possibility of any unmetered air entering the engine.

 

Cobbler I have been thinking about your question?
It appears there is another part that comes off and it has a gasket (I think?). And yes Jaguar does not list it and you can see that from what I posted above from JPART.

Here is the assembly as it sits on the engine. Gives a good view of the two piece intake manifold.




Here is another picture of the intake and I have labeled the two gaskets sets we are talking about.



Now Jaguar ONLY lists the "Lower" intake gaskets as I have labeled in the above picture.
In the above picture I have labeled the "Upper" intake manifold gaskets which Jaguar does NOT offer! Yea why I don't know?

Here is that separate lower intake manifold piece.




The lower intake manifold gaskets look like this. This is the gasket between the head and the intake metal surfaces. Jaguar part numbers MS 96923, AJ89062, 4628235.




Now we got lucky as there are a number of after market suppliers of the upper intake gaskets. But there is some confusion about exactly what they look like. So again you need to get a picture of the upper gaskets so we can compare them. I have seen several different styles for sale on EBay.

Here is the plastic part of the intake manifold with the gasket in place to help show what you need to find out.




Here is a set for sale. These are NOT Jaguar produced parts.
Upper Intake Gaskets

If you can get the information needed we can see what to order.
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Just picked the car up and they did perform a smoke test initially and smoke was pouring out of the gasket ant the base of the riser where it meets the heads. After they replaced the gasket and were getting a little rough idle, that's then they sprayed the plenum/riser area and the engine spit and sputtered, so they came to the conclusion it was that gasket area that too needs replaced. I'm going to leave it as it is for now since the problem goes away after complete warm up, but I'll be monitoring it as time goes on. I'm retired and don't drive it that much. If someone wants to buy it, I think I may entertain the thought and move on.

 

From all the research I've dome the past few days, it seems the 2003 4.2L could have had two different plenum to riser gaskets, like this link you attached in your first reply 4.2L NA Intake Gaskets The green ones at the bottom of this link are the ONLY ones Jagbits offers and the orange ones are nowhere to be found from I researched. So, if there are two different ones for the 2003 4.2 why does Jagbits only offer one style, that's what keeps me from buying them. Sure would hate to buy those from England only to take it apart and find I nee the orange ones.

 

Okay, I just got off the phone with TJ from Jagbits, which is NOT in England but Michigan with warehouses throughout the US, and he said the green gasket with the black square, like in the link provided 4.2L NA Intake Gaskets bottom pic is for 2003 thru 2008 S-Type 4.2L. They are NOT a Jaguar OEM part and he did not know who makes them but for the many he has sold he has never had and complaints. So I feel this https://www.jagbits.com/product/PLENUMSEAL-KIT.html is the best way to go for my issue. Thoughts?

 

Yes Cobbler that is exactly what I posted above?
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