Smell of fumes/petrol

Tue Feb 14, 2006 7:19 am

Bit of help if anyone can please.... When i drive with the window down i get a real strong fume/petrol smell coming into the car, window up cant smell it. Any ideas?

Tue Feb 14, 2006 7:29 am

Is the tank rusting near the filler pipe?

Tue Feb 14, 2006 7:49 am

no doesnt appear to be... i used to get a smell of petrol in the car when i filled it to the neck and accelerated hard and thot this was the problem but i dont fill it as much now and this has gone away, however driving along with the window down theres a strong fumy smell even when the caqr is running with minimal fuel in the tank. It's only there when driving, not when sitting still or when idling with the bonnet open etc, no trace of the smell

Tue Feb 14, 2006 4:36 pm

the fuel pipes to the fuel filter could be perished and leaking or as i had on mine the return pipe back to the fuel tank had rusted through both of these are midway along under the car and under your windows

Tue Feb 14, 2006 4:45 pm

My bet's on the pipe from the fuel filter to the injector rail...

Tue Feb 14, 2006 9:04 pm

gazza wrote: the return pipe back to the fuel tank had rusted through

Be interesting to know where you get your car MOTd.

Tue Feb 14, 2006 10:21 pm

This problem on e30's is normally caused by the swirl of fumes at the back of the car . If you had your car in a wind tunnel it would be easy to see ! as the car moves the exhaust fumes swirl up around the boot area .
When you open a window or sunroof this causes a flow of air out of the car pulling the fumes from the boot area into the cockpit and out of the window .
First thing to check is the boot seal , or you may have a hole in the rear valence etc (fill with expanding foam ) .

Hope this helps .

Regards Steve .

Wed Feb 15, 2006 7:21 am

gazza wrote:the fuel pipes to the fuel filter could be perished and leaking or as i had on mine the return pipe back to the fuel tank had rusted through both of these are midway along under the car and under your windows

Fuel pipes are ok, i checked these over when i changed the fuel filter during service a couple of months ago and the car was mot'd a few months ago just before i got it and our mot's are government run so they are pretty strict. The fumes swirling around the back of the car sounds a possibility, as i said it's only when driving, when the car is sitting still and idling there is no trace of the smell from anywhere around the cockpit, under the bonnet or under the car

Wed Feb 15, 2006 8:58 am

Check if your fuel pump (the one under the rear seats) is firmly fastened and that the o-ring around it is OK.

Wed Feb 15, 2006 9:36 am

oskard wrote:Check if your fuel pump (the one under the rear seats) is firmly fastened and that the o-ring around it is OK.

If this was the cause of it would the smell not be more apparent inside the car with the windows up?

Wed Feb 15, 2006 2:58 pm

When I found this fault on an m3 I used a gas detector and put it in the boot , when I drove along it was fine but as soon as I opened a window this caused a flow of gasses through the car and set off the detector .
It also did the same with the detector on the back seat . I traced it back to a very small hole in the rear valence just above the rear box , as soon as I filled it no more fumes ! .
I've since been told by a German e30 specialist that its a well known problem even when these cars were new . A worn boot seal could also do it .
Regards Steve .

Wed Feb 15, 2006 4:31 pm

mysteron35 wrote:When I found this fault on an m3 I used a gas detector and put it in the boot , when I drove along it was fine but as soon as I opened a window this caused a flow of gasses through the car and set off the detector .
It also did the same with the detector on the back seat . I traced it back to a very small hole in the rear valence just above the rear box , as soon as I filled it no more fumes ! .
I've since been told by a German e30 specialist that its a well known problem even when these cars were new . A worn boot seal could also do it .
Regards Steve .

Thanks Steve, i'll empty the boot and look for any holes all around that area.

Wed Feb 15, 2006 11:26 pm

I use to smell heavy petrol smell in my car cabin, I changed the pipe going to the injector and the return pipe. I saw the pipe to the injector was cracked and petrol was smearing.

the smell inside the cabin went off. But when I drive windows down I could still smell the petrol, so I changed the 2 rubber hoses at the fuel pump.

the smell is still there with the windows down but only when I pump full tank. Once the tank is 3/4 full the smell is no more there.

I suspect it could be the rubber hose at the fuel filler pipe that connects to the main fuel tank. I have found the rubber hose for it and will be fixing coming week end. Will let you know if the problem is solved.

cheers

Thu Feb 16, 2006 8:28 am

haffeel wrote:I use to smell heavy petrol smell in my car cabin, I changed the pipe going to the injector and the return pipe. I saw the pipe to the injector was cracked and petrol was smearing.

the smell inside the cabin went off. But when I drive windows down I could still smell the petrol, so I changed the 2 rubber hoses at the fuel pump.

the smell is still there with the windows down but only when I pump full tank. Once the tank is 3/4 full the smell is no more there.

I suspect it could be the rubber hose at the fuel filler pipe that connects to the main fuel tank. I have found the rubber hose for it and will be fixing coming week end. Will let you know if the problem is solved.

cheers

Im getting the smell regardless of the amount of fuel in the tank, i think it must be down to fumes leaking into the cabin somewhere as suggested

Sat Feb 18, 2006 4:45 am

OK guys, I installed a new rubber hose at the connection between Fuel Filler Pipe and the Tank. Yes the old rubber looked little perished at the tank joint but overall it is still good.

Now after installing I pumped full tank as usual right up to the neck, the smell is still there

While fixing the rubber hose we noticed the tank top where it has its lid welded is leaking .. So now I am very sure it is the tank that is leaking. I am going to get another tank just be safe. mine is a 55ltr tank.

Sat Feb 18, 2006 10:34 am

haffeel wrote:OK guys, I installed a new rubber hose at the connection between Fuel Filler Pipe and the Tank. Yes the old rubber looked little perished at the tank joint but overall it is still good.

Now after installing I pumped full tank as usual right up to the neck, the smell is still there

While fixing the rubber hose we noticed the tank top where it has its lid welded is leaking .. So now I am very sure it is the tank that is leaking. I am going to get another tank just be safe. mine is a 55ltr tank.

Unusual place for the tank to leak. It's usually the little inlet stub pipe or the tank just around where it joins that the holes appear.
Are you sure it's not running back over the tank from a split fuel pump O ring?

Sat Feb 18, 2006 3:39 pm

Brian, I am pretty sure cause I could see petrol dripping. the tank top side where the weld is, leaking and it is wet there.

Wed Feb 22, 2006 3:35 pm

ok I am wrong, today we pin pointed the leaky spot, it is the O ring holding the fuel sender. Once replaced a new O ring now the leak there no more.

what puzzles me is, when no one is fiddling down there, how can the O ring perish

Wed Feb 22, 2006 6:44 pm

haffeel wrote:ok I am wrong, today we pin pointed the leaky spot, it is the O ring holding the fuel sender. Once replaced a new O ring now the leak there no more.

what puzzles me is, when no one is fiddling down there, how can the O ring perish

Not unusual. The "rubber" degrades, cracks appear, and eventually it will split. Cheaper than a new tank.