Petrol smell in cabin

[Stud_Daddy]

Alright people, this is a tough one. 3 points to the one who helps me figure this out.About 1 month ago while I was at an accessory shop, there was suddenly the very strong smell of petrol in my car. Checked everywhere, but couldn't trace the source. There was nothing else wrong with the car, and so I ignored it, and the smell went away after about an hour. Ever since, I've noticed that there is the faint smell of petrol inside my car cabin when the car stops at traffic lights.Also (and I don't know if this is related), there were 2 instances recently when my car went dead at the parking lot......almost like petrol was reaching the engine. After a few starts and depressing the accelerator, all was fine. Even drove the car from Penang to KL and back.Had my petrol filter changed during my last service.....also about a month ago before all this started. Don't know if that's the source of the problem. Seems like maybe there's a leak somewhere (duh), and I check for puddles of petrol on my car porch ever morning but there is none.Any ideas? Final resort; trade in my crotch sniffing dog to a petrol sniffing one.

 

[SMG330i]

Hey bro, i've the exact same problem with all the above mention... I found out the petrol smell only when i idle the car for at least 5 mins or above, then i will get the smell in the cabin. There is no leakage or watsoever. But i notice the smell comes from behind... Anyone can help us ?

 

[GT-E39]

According what you post ,You try check the FUEL PUMP oil seal rubber .

 

[tc@torpedo]

What car do you drive? I had an E36 once with the same prob. Under the back seat (which you have to remove) there is a cover. Open this cover and there is rubber hose which channels fuel. This hose over time needs to be changed as it will start to leak leaving a strong smell of petrol. Why the smell stops after a while is cos you stop driving. But once you're on the move, the petrol starts flowing again causing the smell to come on. Hope this helps. Cheers!

 

[Stud_Daddy]

Guys thanks for the excellent advise! Now that i think about it, I remember the accessory shop guys messing with the petrol pipe cover thingy under the back seat when they were applying Dynamat there about a month ago. I'll get it checked as soon as my mechanic opens shop and I'll post an update here.

By the way, I drive a 1999 E46 (318i).

 

[sesat88]

Guys thanks for the excellent advise! Now that i think about it, I remember the accessory shop guys messing with the petrol pipe cover thingy under the back seat when they were applying Dynamat there about a month ago. I'll get it checked as soon as my mechanic opens shop and I'll post an update here.

By the way, I drive a 1999 E46 (318i).

ask you mechanic to check all your inlet/outlet fuel hoses. Some may have harden or the clip is gone.

 

[LCP]

Sigh, my car just developed the same problem... gonna hafta get it checked out this coming Saturday. Just got the fuel tank gaskets/seals checked out back in Dec, no problem then.

 

[Stud_Daddy]

Update: Two mechanics couldn't find any leaks anywhere.

Finally, one says its my petrol cap. I don't have the original BMW cap on my car, and mine is not a very good fit. The rubber lining is a little worn out now. According to him, the petrol smell comes into the cabin from the gaps in the cap .....which is quite surprising because the cap is outside the car! So anyway, to test his theory I've ordered a new original BMW cap, and it should arrive on Tuesday.

According to him, the reason the smell is strong in the hot afternoon is because the heated petrol vapour seeps out from the loose cap and into the cabin. His theory is that the smell is not very strong at night (which is actually true).

 

[LCP]

Mine's definitely not from the petrol filling cap... It's very strong outside the car, but not from inside... It's like it's from the tank area, but if the wind is blowing, especially from rear to front, it's very difficult to tell the source.

 

[sesat88]

Mine's definitely not from the petrol filling cap... It's very strong outside the car, but not from inside... It's like it's from the tank area, but if the wind is blowing, especially from rear to front, it's very difficult to tell the source.

....then stand down wind to tell the source la...

but seriously, i also am facing the same issue.... but the unburnt is coming from the exhaust and am having car shudder at idle(rpm rock steady). I think there is a few things to consider here.... NIAMAH. . this is really post GONG XI FA CHAI angpow....

 

[jarance]

Alright people, this is a tough one. 3 points to the one who helps me figure this out.

About 1 month ago while I was at an accessory shop, there was suddenly the very strong smell of petrol in my car. Checked everywhere, but couldn't trace the source. There was nothing else wrong with the car, and so I ignored it, and the smell went away after about an hour.

Ever since, I've noticed that there is the faint smell of petrol inside my car cabin when the car stops at traffic lights.

Also (and I don't know if this is related), there were 2 instances recently when my car went dead at the parking lot......almost like petrol was reaching the engine. After a few starts and depressing the accelerator, all was fine. Even drove the car from Penang to KL and back.

Had my petrol filter changed during my last service.....also about a month ago before all this started. Don't know if that's the source of the problem.

Seems like maybe there's a leak somewhere (duh), and I check for puddles of petrol on my car porch ever morning but there is none.

Any ideas? Final resort; trade in my crotch sniffing dog to a petrol sniffing one.

Try pumping with to full tank first and then check under the back seat.

 

[Stud_Daddy]

Try pumping with to full tank first and then check under the back seat.

Already done that. No leak found.

 

[affan66]

have you checked:

fuel lines - from pump to engine / from left to right pump / in between fuel filter

fuel pump rubber ring (likely not since no leak found at full tank).

 

[Stud_Daddy]

have you checked:

fuel lines - from pump to engine / from left to right pump / in between fuel filter

fuel pump rubber ring (likely not since no leak found at full tank).

Nope.....haven't done all that. I suppose I'll do that if the petrol cap solution doesn't work.

 

[LCP]

Okay, here goes, got to the root cause of the petrol smell on my E36... The plastic top of the fuel gauge sender unit (on LHS tank) has developed small cracks and fuel leaked out of it whenever the petrol tank is full, or nearly full...

Here are some pics:

1st pic below is my leaking unit, still on the car, has leaked for a long time I guess judging from the amount of dirt accumulated. You can see so much petrol there...

This pic below is the same unit above after it has been taken out and washed...

Next pic below is the temporary replacement unit provided by Chu Seng Auto here as they don't have stock of a new unit. As it turned out, this unit is also leaking, but not as bad...

A new unit has been ordered, will go and fix next Sat... any idea how much is it? Workshop didn't provide me any quote.

 

[manjit]

I think i might have the petrol smell as well. Have this smell during driving and the windows are down. would eventually go off after i wind up the windows, and it happen only when the fuel indicator is above half and while driving.

 

[Stud_Daddy]

Ok here's an update; I changed my petrol cap to a new one and the smell is gone. Its been 10 days now. The old one didn't have a good fit anymore and the fumes were escaping. Simple as that. I almost wish I had a more complicated solution, but frankly, that's it. Paid MYR 70 for the new original cap.

 

[LCP]

Just got my left hand side fuel gauge sender unit changed earlier this morning, to a brand new unit. No more leaks, for a long time, hopefully...

 

[Bmmad318i]

How much for the replacement of the sender unit??

 

[LCP]

RM280 for that part. RM45 for labour. RM2.25 for tax...