www.jec.org.uk

I would be most grateful for experience of, views concerning and answers to a problem that I am experiencing of diesel/traffic fumes ingress to the cabin of my X358 2.7d. The problem occurs very intermittently and is most commonly experienced when travelling slowly, or at rest, say in traffic or at a set of lights.

I have looked through this X350 forum BB for information on the above and have found little if anything. However, on the S Type and XF BBs of JEC and also some other forums for Jaguar owners there are quite a few postings concerning diesel fumes in the cabin. Though, most of these postings are from some time back.

From what I can glean from these postings and on-line conversations, the most likely cause of this problem is a failure of the flexi-joints on the 2.7d CATS.

Q Is this correct?
Q What other cause(s) might there be?

I must admit that I will be disappointed if this is the problem as my local independent Jag specialist had to replace the flexi-joints on my CATS only 2 years ago as they ‘fell apart’ when the CATS were removed for some reconditioning work on the turbos and manifold to be undertaken. BUT this gives rise to this overall request for advice and especially the following points and questions.

If this does prove to be the cause of the problem there seem to be two similar but slightly different remedies/replacement parts one can obtain for these flexi-pipes. One has a very much shorter section of flexi-pipe and the other is effectively solid pipework.

[My understanding from these postings that Jaguar, originally, did not supply a replacement for the flex-joint only but instead supplied a whole new CAT including the flexi-joint at great cost. They subsequently, offered a replacement part, which I understand was modelled on the one that was being supplied by independent Jag/exhaust specialists with the much reduced flexi-joint.]

However, the various providers of the two different sorts of replacement make differing claims and counter claims for their parts.

The producers/suppliers of the part which retains a small part of flexi-tube in this joint says that this is necessary to prevent vibration and resonance in and from the exhaust system. The producers/suppliers of the ‘solid stainless tubing sleeve’ solution say that this is not the case as the CAT is firmly anchored and that further that this method, in addition to solving the problem will never corrode or crack.

Q I wondered if anybody had had experience of replacing their flexi-joints on a 2.7d and, for the obvious reason due to my experience of having had these replaced only 2 years ago, if, in their experience the claims of the ‘solid stainless tubing’ variety producers suppliers were borne out? and who they had used?

I would be most grateful for any input as I am going to get the independent Jag garage that services my car to have a look for any evidence of fumes escaping from these flexi-joints when they have the car up on the ramp when it is serviced, diffoil changed and MOT’d in two or three weeks’ time.

Finally may I say thank you and how useful I have found the BBs on the JEC site. They have been ,in fact, a necessity, as I have come across those various issues that need sorting when one owns a ‘non brand new’ car, especially with the change in parts, specifications and recommendations over time, on everything from engine oil to engine mounts. They are also invaluable to me in providing details and recommendations of independent Jaguar specialists/experts who are able to provide services that I cannot get locally - even though it means I have had to travel a distance to get certain things done. There is a paucity of Jaguar independents/experts in my direct area.

Despite all these issues and things that have to be sorted out from time to time I must admit that my X358 has turned me into a Jaguar convert. I only wished I had bought one earlier in my motoring life

I suspect there's an alternative source of fumes at this time of year. The XJ has an AGA or at least an oil-burning stove somewhere in the right hand front wing. (Officially it's an Auxiliary Heater or Fuel Fired Booster Heater.) As far as I know, it's triggered in low temperatures when you have the climate control system set to "Auto", and used to warm the cooling water, presumably to warm the cabin on a cold day until the engine's hot. (That's needed because diesels being more efficient, they dump far less waste heat into the cooling system. My workshop manual implies they're also fitted to petrol cars.) Personally, I just set the system to feet+windscreen in the winter to reduce misting and stop wasting fuel on heating the memsahib and me, and use the heated seats.

I think it also comes on in even colder conditions irrespective of the climate control setting, to warm the fuel system.

I don't know where it vents its fumes; there ought to be a quaint black stove pipe coming out of the wheel arch, but I've suspected in the past that it's near enough to the heater fan plenum for fumes to be sucked into the cabin, as I've noticed a fuelly smell on a few occasions.

Paul thank you - I have had experience of said heater on cold mornings, when it can pump out wreaths of smoke (and smell) - the fumes coming out from under the front wings. The first time it happened, on a very dark and cold winter morning, it was like the opening title sequence of each episode of ''The Equaliser', the old TV series starring David Woodward (for those, like me, old enough to remember it) where he was silhouetted standing in front of his Jaguar (with the headlights on) on a very misty morning.

It may be this heater but since it is tending to happen intermittently and most usually when the engine is at operating temperature, I tend to suspect not. The past two times it has been particularly noticeable have been when driving into 'town traffic'; in both cases after a reasonable run of 30 minutes plus,down dual carriageway/motorway.

I have just changed my pollen/cabin filter to see if this might not be up to snuff and am going to get G&D at Welwyn Garden City to take a look at the flexi-pipes to see if they can see a problem with them - but as I said in my original post since these were done only two years back I am hopeful/expecting that these should not be the cause of the problem

Hi,

My X358 also suffered from this problem on and off. When this initially occurred a few years ago I replaced both flexi joints with solid pipe repair kits, this stopped the fumes but there was a small increased resonance from the exhaust. My wife couldn't notice it but it drove me mad!

About 12 months ago I managed to pick up a couple of cats with good flexi joints and fitted these solving the resonance, however, about six months ago I noticed fumes in the cabin again so assumed that one of the fleix joints had gone.

About 4 months ago I finally decided to tackle the EGR valves as I had had a couple of intermittent warning codes over the previous 18 months. I thought that at the same time I would replace the nearside cat with the solid pipe I had taken off 8 months earlier as I could smell the fumes from the nearside of the engine with the bonnet up.

On removing the nearside EGR cooler I noticed that it was black with soot which I put down to the cat flexi joint leaking. However, this time the solid pipe made no difference to the fumes! They were most noticeable when the engine was hot, particularly when slowing down from Motorway speeds. A couple of weeks after changing the EGR valves I took off the engine & injector sound proofing to see if I could see the source of the leak and noted that the EGR cooler was again black and fumes seemed to be coming from the back of the engine near where the turbo bolts to the manifold.

I decided that removal and replacement of the EGR valve, cat, turbo and exhaust manifold gaskets was probably the best way forward but was not looking forward to doing it in view of the risk of snapping manifold studs.

I was then struck with the idea that perhaps the leak was from the pipe that goes from the manifold to the EGR cooler. As the pipe and gasket are available for less than £40 I thought I would give this a try before embarking on anything else.

A few hours last Sunday were enough to get a shiny new pipe fitted in place of a very black old one. I thought I could see where fumes had been escaping past the gasket so may have got away with just replacing that but given how fiddly it is to get to I am glad I had chosen to buy the pipe as well as the gasket rather than having to do it twice if it was the pipe leaking rather than the gasket.

This has finally cured the exhaust fume leak, I just have to put back on a cat with a flexi joint now to get rid of the annoying resonance!

The nearside pipe is C2C37870 and the gasket is JDE3756.

Hope this helps.

David

David, thank you. It sounds as if the occurrence of the problem is happening at the same time as mine. e.g. when the engine is warm after motorway runs. I have also had a 'restricted performance' warning light come on a couple of times recently (in both these cases a few hundred metres after setting off from cold) which extinguished itself when the ignition was turned off and left for 5-10 seconds. So like you think there might be a potential issue with the EGR valves.

My vehicle is in today for service, diff oil change and MOT and have asked my local Jag specialist in Welwyn to have a look for the possible source of these fumes and the 'fault codes'. Will await to see what they say and if it chimes with what you found, or not.

As an aside, I took my car into a Jag specialist in the home counties - some distance from me - the other week for some remedial work on the interior. Whilst there, I asked them the question about the flexi-pipes and from experience they have found that these fumes can sometimes be caused, even when the 'amended' version flexi-pipes have been fitted, by leakage from around the jubilee clips where the 'amended' version flexipies are connected to the cat. They overcome this by welding the 'amended' version flexipipe connection to the cat.

Glad to hear you got your issues sorted.

Regards

FWIW, I've just got my diesel XJ back from the dealer after having a broken flex joint replaced with the Jaguar kit. The fumes in the cabin were getting stronger, especially coming to a halt on the slip road after pounding down the motorway. Hopefully this application of money will have cured it.