When ever we tow a caravan up hill and the engine gets hot we start to get fumes coming out the air vents. I have recently replaced the o-rings on the connection to the leak-off pipes and have confirmed that there is no diesel on the engine so this is not the source.
I guess it could be oil dripping down from the breather pipe onto a hot part of the turbo or engine but how do the fumes so easily get into the cabin even when the car is doing 100km/h.
I am going to do a degrease and change the clamps on the breather pipes but I was wondering if anyone had come across this and found a solution. The car has done this for the last 4 years but only when towing or going up really steep hills but it has to be a health hazard, even with the windows down. Please help.

Could this be exhaust gases being blown in through the cabin fan due to turbulence of the air in between the car and caravan as it only happens when towing?? I would keep the windows up and make sure you have replaced the pollen filter and just have the recirculation fan on, the fact it only does it when towing and not at other times seem like the caravan is stopping the exhaust gases from blowing away from the rear of the car???? just a thought. 2013 FL2 XS.
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I've had the burnt oil smell on mine and I believe
it's caused by the oil residue from the large pipe at the back top
of the engine,
But I only notice it outside the car and after a long steep hill
or motorway dash, which would mean the turbo has worked harder and therefor got hotter!!
as said is your cabin filter in situ and clean? DAVE.

The fumes could come in from the rear of the car. We have noticed in the outback with the red dust, if we put the ventilation on recirculation we get the dust smell in the car. If any window is open a bit air gets sucked out.

Best to close windows & have some air coming into the car through the ventilation & clean the filter a bit more often if needed.

Also when I have removed the boot trim panels there is a lot of red dust which has come in from the rear.

Also, make sure the rubber seal at the rear end of the bonnet is sealing properly. It divides the engine bay to the ventilation intake area.

Red dust shows where air comes into the cabin. Through door handles, around window trims, somewhere under the rear passenger door sills & boot as already noted. Procrastination, mankind's greatest labour saving device!

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Rommel wrote:

Could this be exhaust gases being blown in through the cabin fan due to turbulence of the air in between the car and caravan as it only happens when towing??

That is a valid point thank you but I should have said is a low profile windup caravan (Jayco Eagle) and this seems to be more tied to engine temperature. I've been monitoring the engine and transmission temperatures and it only happens when the engine is hot. I do need to change the pollen filter though Thanks!

Dave47 wrote:

I've had the burnt oil smell on mine and I believe
it's caused by the oil residue from the large pipe at the back top
of the engine,
But I only notice it outside the car and after a long steep hill
or motorway dash, which would mean the turbo has worked harder and therefor got hotter!!
as said is your cabin filter in situ and clean?

Lightwater wrote:

Also, make sure the rubber seal at the rear end of the bonnet is sealing properly. It divides the engine bay to the ventilation intake area.

Red dust shows where air comes into the cabin. Through door handles, around window trims, somewhere under the rear passenger door sills & boot as already noted.

If you take the battery cover off, you can see the hole through the fire wall into the cabin for the ventilation.


Inlet almost in the middle of this photo.

Click image to enlarge

ribama1 wrote:

Am I correct the fresh air comes in over the bonnet and through intakes below the windscreen?

ribama1 wrote:

Dave47 wrote:

I've had the burnt oil smell on mine and I believe
it's caused by the oil residue from the large pipe at the back top
of the engine,
But I only notice it outside the car and after a long steep hill
or motorway dash, which would mean the turbo has worked harder and therefor got hotter!!
as said is your cabin filter in situ and clean?

Our circumstances seem similar Dave. The fumes only start when engine is really hot... its almost like the fumes are being driven or sucked into the intake for the air vents. The pollen filter is about 3 years old. But this was happening when it was new also. Thanks for replying.

I had a problem with fumes in the car, but this was happening almost from start up, rather than only when engine very hot. Looking back at the work sheet it was found that the 'breather seal' was leaking, and all OK once the O ring was changed. I don't know if 'breather seal' is enough to identify the part/area.

Lightwater wrote:

Click image to enlarge

The foam sealing on the underside of the plastic engine bay panel may have deteriorated as well. To get this off is an easy job but you do need to remove the windscreen wipers, which may need some careful persuasion.

Lightwater wrote:

ribama1 wrote:

Am I correct the fresh air comes in over the bonnet and through intakes below the windscreen?

In some respects. It's a pretty clever arrangement once you see what's going on underneath. Air first comes in on the left through the plastic grill around the cover for access to the brake fluid. Then below is a tray to drain water in the air away attached to the underside of the main panel, this unclips so can be cleaned.

After that air is drawn to the battery side of the car, this also helps circulate air around the battery to keep it cooler. Then sucked into the cabin.

This whole process changes air direction many times to throw off dust & pollen etc before it gets to the cabin air filter. This area in my car was absolutely filthy.

Dave47 wrote:

ribama1 wrote:

Dave47 wrote:

I've had the burnt oil smell on mine and I believe
it's caused by the oil residue from the large pipe at the back top
of the engine,
But I only notice it outside the car and after a long steep hill
or motorway dash, which would mean the turbo has worked harder and therefor got hotter!!
as said is your cabin filter in situ and clean?

Our circumstances seem similar Dave. The fumes only start when engine is really hot... its almost like the fumes are being driven or sucked into the intake for the air vents. The pollen filter is about 3 years old. But this was happening when it was new also. Thanks for replying.

All I can say is I get the smell after prolonged fast driving or hill work,
But do not get the smell in the cabin!!
So 2 issues is oil escape/misting and fume ingress into the cabin,

SimonB wrote:

I had a problem with fumes in the car, but this was happening almost from start up, rather than only when engine very hot. Looking back at the work sheet it was found that the 'breather seal' was leaking, and all OK once the O ring was changed. I don't know if 'breather seal' is enough to identify the part/area.