Engine

[Evansmr]

The other day I had a lot of fumes coming out from under the engine bay at the near side front that lasted possibly 5 to 10 seconds. It was so much that I initially though the engine was on fire or a radiator hose had burst. The weather was cold.

It was not burning oil nor petrol fumes and the vapour dispersed quickly. It did smell though and the fumes entered into the passenger compartment via the air intakes. I have lost no fluids at all and the engine runs sweetly. I tried to repeat the event and it happened again on a much smaller scale the next day. It only happens when the engine was idling and the car stationery but maybe it happened whilst moving but could not tell..

I contacted the local Jaguar dealer in Basingstoke to book in the car and they said there is an issue with a pre-heater located near the vent intakes and it does happen on cold days on the 2.7 diesels. I don’t know if the pre-heater is on the diesel circuit. I would have thought though that any circuit would be a closed system thereby not letting out any fumes but what the garage described was what I had experienced. They said it only happens for s short time in cold weather.

I am posting this forum to see if what I have experienced and what was explained by the Jaguar dealer has happened on S Types Diesels before and was correctly explained and to see if there is anything that can be done about it or if it is one of those quirks that I must live with.

I have had the car since March 2009 and it has been faultless. It is a 2006 model (55 plate) and still under Jaguar Used Car Warranty.

[J44EAG]

I`ve heard of this before with the diesel 2.7 unit.

As I understand it, this is normal when the heater operates in cold weather.

Fumes are unavoidable and it can be a right old stink! We have similsr systems on old boat engines. On some of the older models, a puddle of diesel was set alight and the naked flame sucked into the inlet manifold. With that type of crude unit, it was not unusual to have a small bombfire going before the engine fired and comsumed the maelstrom.

The Jaguar system is somewhat more high tech.

I personaly don`t think you have a problem.

Kind regards,

Mike Kennedy JEC S-type Forum Co-ordinator.

[Davidvvp]

I have exactly the same probelm on my 55 reg 2.7 diesel S-type but this winter the fumes seem to be very excessive - - clouds of bluish smoke.
I have a copy of the S-type Technical Guide which explains the operation of the heater in quite some detail. It is quite sophisitcated with its own electronic control module
One useful bit of information is that the fuel fired heater can be prevent ed from coming on by turning OFF the Climate Control System until the engine has warmed up. This saves a lot of embarassment!

One question - what is the cause of apparently excessive smoke and can it be ajusted?

Other wise I am extremly happy with the car which I have now owned for 15 months

[J44EAG]

The smoke is caused by fuel used in the pre heater on the diesel and the fuel burns better when a combustion chamber is hot rather than cold.

The heater is used in colder weather the "get the fire" going. Heat is required on a diesel engine start up during cold weather. On my boat, I play a lit blow torch down the air intake on start up in cold weather otherwise the engines just won`t start. Jaguars answer is rather better developed!

Alarming it may seem. Necessary it is!

Perhaps your maintenance people might be able to fine tune the system further.

Mike

[Evansmr]

Thanks for the feedback. I'll try switching off the climate control at start up.

I must admit that I see it only as a slight inconvenience now that I understand the cause. The car is so trouble free that I can put up with this.

Thanks

[etypedriver]

My 2007 diesel emits smoke from the front when first started,the dealer told me it would and is the pre-heater.I think yours is normal,interesting though that turning off climate prevents it,I might try that

[J44EAG]

This is all good information Guys.

Thank you all for your contibutions. This is the prime reason for setting up the S-type Forum.

Please continue to post with your experiences and stories.

Well done all and keep the information flowing.

Mike Kennedy. S-type Co-ordinator.

[jeff1954]

HI
I have a 2.7d but i dont think the pre heater is working as in the winter the engine takes along time to warm up having said that i only live 3.5 miles from my place of work .
Regards Jeff .

[J44EAG]

Hello Geoff.

The pre heater is used to "get the bombfire going" prior to start up. A bit like heating brandy over a flame before pouring on the Christmas pud. Diesel like brandy when cold is difficult to set fire to. Hence the pre heater. The same goes for starting a diesel. No heat, no go!

Several other diesel owners have previously mentioned the subject of getting the engine to warm up in cold weather. That is a diferent subject altogether, as the pre heater has no influence once the engine is up and running. Warm up to standard temperature is influenced by the external air temperature, the engine temperature, the thremostat heat rating and the differential between all factors therein. Change any one of those factors and the speed of warm up will be affected.

At the S-type seminar in March2010 we learned that a choked particulate filter can cause excessive smoke on start up. A point for diesel owners to keep a check on.

I think this link to Flanders and Swann sets the First and Second Law of Thermo Dynamics out nicely. It states the obvious really! Enjoy.

http://www.youtube.com/watch?v=Cb2kBFqr ... re=related

Joking apart, an engine should always be brought up to full operating temperature before being switched off, even if it means sitting in the car for a few minutes to ensure that does indeed happen. If this does not happen, the oil is prone to retain condensation droplets which if left to build up will cause the oil to break down with consiquent premature engine wear.

Hope this helps.

Mike

[jeff1954]

Hi Mike
Thanks for the reply i have never had aproblem starting her up so maybe the preheter is working afterall its just that i have never noticed any smoke . I only do about 4.000 miles a year so i might change the oil and filter on a anual basis giving what you said about the condensation factor

[J44EAG]

For cars used on short journeys, the oil change regime needs to be increased significantly.

With a car used for short journeys of only three or four miles, I would be looking at changing the oil, (even synthetic) at periods of around 2,000 miles only. Short journeys are very destructive to an engine and its oil.

I understand from Nigel that an article I wrote about oil degradation is due to be published in the September edition of our magazine. My findings are quite alarming. Watch out for the article. It is quite revealing.

A case of sleep well and don`t have nightmares!

Change the oil reguarly and you will be ok.

Mike

[jeff1954]

Thanks Mike i will.

Jeff.