Diesel fumes through heater

OK so l have posted this before, last year, but l thought it was sorted.

The exhaust on my 110 TD5 CSW does smell strongly of diesel, but l guess it will....it's a diesel lol

However as soon as l stop moving the smell comes through the heater, if the blower is on.
If the blower is not on l never get the smell even when reversing.

I am at a loss as to how the fumes so readily find their way to the heater intake on the wing, as the exhaust is at the back.

The exhaust has been checked for leaks. The EGR valve has been removed. The MAF unit is new, as is the air filter.
The manifold looks OK and l cannot smell fumes under the bonnet anyway, they seem to be outside.
The ECU has been remapped and no fault codes showed up.
This Defender has had this issue since l bought it a year ago and l have done 12,000 miles.
The engine runs fine and fuel economy is good. The injector harness has been replaced as there was oil in the harness.

I just get this diesel smell in the cabin, unless the wind is blowing it away.

What can l check? I even put some drought excluder along the edges of the bonnet but it made no difference.
Two garages have looked at it and found nothing, one suggested removing the CAT which l let them do, but it made no difference.

Why would your exhaust smell of diesel? It should all be being burned, leaving only exhaust gases. A very small fuel leak will go a long way on the nose and float about a bit.

Fuel pressure regulator back of the head drivers side?
Diesel smell from exhaust suggest injector possible at fault.

One of my flexi spill-off pipes had the tiniest of leaks, wasn't dripping but it was enough to stink out the cab.

Thanks for the replies. Looking at the service history the fuel pressure regulator has been replaced in 2012.
I have looked extensively for leaks but l think the smell is exhaust fumes and not diesel.
The smell is not unusual, when l am on my bike l can smell it when a diesel car goes past.
But on our 90 TD5 it does not get in the cabin so much when the heater is turned on.
If there was a faulty injector would it cause any other symptoms? The engine runs fine, starts fine and does about 27mpg in town driving.

I'm not familiar with the td5, is the crankcase breather anywhere near the blower intake?, is it firmly attached? Faulty exhaust manifold or gasket would cause smell too, normally accompanied by an obvious noise though.

Has the heater intake ductwork come adrift under the bonnet so the heater is pulling from the engine bay rather than fresh air?

As above. You should not be able to smell exhaust fumes standing beside the heater air intake, unless the wind is blowing it back towards you. So it follows the heater should be drawing in fresh air from there. the bulkheads and ducting seals aren't up to much, have a look between the blower intake and the wing intake point.

OK will do.

However l have stood around the vehicle and the exhaust fumes seem to make their way from the back to the front within a few seconds of stopping.

So l take it all diesels emit exhaust gases that you can smell, as it happens whenever a diesel car goes past. It is just wierd on this Defender how they seem to make their way to the front.

All the underbonnet pipework has been checked, the last time they took off the engine covers to get a better look, fitted a EGR bypass kit, a CAT bypass pipe, and a new MAF sensor and air filter

On my old td5 disco the downpipe split behind the flex section mesh was hard to find, not sure if defender has a flex section in the downpipe? Also would bet your heater trunking has naff foam seals that have split

lightning said:

OK so l have posted this before, last year, but l thought it was sorted.

The exhaust on my 110 TD5 CSW does smell strongly of diesel, but l guess it will....it's a diesel lol

However as soon as l stop moving the smell comes through the heater, if the blower is on.
If the blower is not on l never get the smell even when reversing.

I am at a loss as to how the fumes so readily find their way to the heater intake on the wing, as the exhaust is at the back
.

Click to expand...

lightning,
Are you sure it is diesel you can smell ?
Just a thought is it as soon as you start up that this smell occurs if not and only after a distance is covered. Then it could be a brake binding on the side of your heater intake causing the pads to heat up and smell, the fumes from this being drawn into the cab.

Tim4x4 said:

lightning,
Are you sure it is diesel you can smell ?
Just a thought is it as soon as you start up that this smell occurs if not and only after a distance is covered. Then it could be a brake binding on the side of your heater intake causing the pads to heat up and smell, the fumes from this being drawn into the cab.

Click to expand...

good call, they stink bad also makes things hot. feel the wheel/rim after a drive if it is warmer than the others there you go excessive dust on a wheel will be a clue

No the brakes are fine, not getting hot.

Tonight l disconnected the MAF unit and the fault seems much reduced also the Land Rover runs the same without the MAF connected, if anything a bit smoother on acceleration but that might be me.

It's a VDO one which was three times the price of the cheap ones, only been on about three months. Could it be defective already?

lightning said:

No the brakes are fine, not getting hot.

Tonight l disconnected the MAF unit and the fault seems much reduced also the Land Rover runs the same without the MAF connected, if anything a bit smoother on acceleration but that might be me.

It's a VDO one which was three times the price of the cheap ones, only been on about three months. Could it be defective already?

Click to expand...

I seem to recall you posting a statement that if it runs the same when the MAF is disconnected then the MAF is faulty simple!!!
You say it runs the same or even better if disconnected then the MAF must be faulty, three months old then take it back.
I guess you will have to discuss the rights and wrongs of how you know it to be faulty and be met with no sir they do not work like that but stick out for a replacement.

Are you sure its not oil drips on the exhaust?

I don't recall posting that.

However my local specialist are pretty good with warranty items, but if not l'm not paying another £90.... I'll buy one of the £30 ones that they also sell.

look at the ducting to the heater box, it's only a bit of sponge or foam and not very air tight, it's probably sucking in under bonnet fumes.

if so, get your engine running and stick your hooter under the good and start looking for diesel leaks. you shouldn't smell diesel from an exhaust.

Let's get this clear. I think that you've got people thinking that you can smell diesel fuel, but actually it's diesel exhaust fumes that you're talking about.

Have you checked for exhaust leaks (hand over the tailpipe and listen)? If that's OK then I'd be looking at the back and rear side door seals.

Hand over tailpipe could be a bit hot. Use a pad of cloth.

I tried the exhaust test and no leaks showed up.

Driving with the MAF disconnected tonight, the smell seemed less but l was getting clouds of grey smoke under hard acceleration.