Petrol Smell on Switch Off?

[Lean Machine]

I recently noticed that when I switch the engine off there is a smell of petrol that seems to linger in the garage for days. I have checked around, under the bonnet and around fuel tank and pump area but I can't actually see any leaks. I have had a similar problem on a previous TVR but not as bad, the problem didn't bother me at the time and so was never resolved. On this one the smell is quite bad. Any ideas or suggestions please before I book it into a garage and get my wallet out again.

Tony. TCB.

[Jonny weggie]

Tony why dont you tape over your [fuel]overflow pipe, on left hand side [close to bottom spoiler] looking from back,and see if that's been the cause of the smell.

jonny.

[gromit wedge]

My 350i had a leak from the left hand tank. There is a small fuel pipe that was fouling the wheel and had partially rubbed through. I had never noticed the pipe was there until the mot tester pointed it out. Might be worth a look as I never noticed it leaking onto the floor.

[mrzigazaga]

Hi Mate..Does it happen all the time or only when you have over half or near full on the gauge?..There is a breather that goes to atmosphere 2" down from the filler cap and when cornering..(Even gently) the petrol will splash up and get into the pipe..Have a sniff around the fuel cap to make sure the rubber seal is ok on the cap!!..If you can take the rear trim off behind the drivers seat and inspect the pipe and clips on the filler neck..Although you would smell raw fuel to the right of you most of the time if this was the case..especially when stopped..Cheers..Ziga

[Lean Machine]

There is no smell when driving, or if there is I can't smell it because it,s out in the open. Once the car is switched off, it's still not noticeable out in the open, but when I park it in the garage after a while the smell of fuel increases. I jacked it up this afternoon and had a good look underneath. All the pipes including the one that runs up to the engine are the braided type and in good condition with good clips on all joints. Everything around the fuel pump and filter look clean and newish. The tanks however are old and suspect, but I can't see any leaks. I also checked under the bonnet and all looks good. It's a bit of a mystery at the moment but I'm taking all your comments on board. Keep them coming so as I don't overlook anything. Otherwise, if I don't solve this problem soon my wallet could suffer. Though I've had this car for over a year, I usually park it in a block of garages away from home, but just recently I've been bringing it home and the garage here is joint to the house and so the smell travels, hence it has started to bother me. I'll continue searching.

Tony. TCB.

[KelWedge]

I had that a few months ago, had a look under the car, nothing, then started up and looked under again and it was flying out at the pipe as it came out of the pump.

[Lean Machine]

KelWedge said:

I had that a few months ago, had a look under the car, nothing, then started up and looked under again and it was flying out at the pipe as it came out of the pump.

I've looked under the bonnet when the engine was running but never under the car with the engine running. I will try that and see if I can spot a leak. Thanks.

Tony. TCB.

[RCK974X]

My wedge ('82 280) ALWAYS smells a bit (when stationary) when tank is more than half full. Checked many times, and there is no leak, it just vents smells out the breather pipe (which in mine goes out under the rear valance on the offside). I've decided it's one of those endearing features...

[Lean Machine]

I had a little sniff around tonight while the car was in the garage. My sense of smell is extremely good which is why I think I must have been a dog in a previous life. The strongest smell seems to be coming from under the top vent of the bonnet. Now, I've looked under there and although the main fuel line and the return are there, I can't see a leak. How strange is that? any suggestions?

Tony. TCB.

[adam quantrill]

You can get vapour building up in the plenum and then gradually permeating back out through the air filter.

As an antidote let the engine idle for 30s or so before switching off. Even better if you have a kill switch for the pump - use that - or pull the fuel pump fuse - then the engine will die when it uses up the fuel in the line. Then turn it off.

[Lean Machine]

adam quantrill said:

You can get vapour building up in the plenum and then gradually permeating back out through the air filter.

As an antidote let the engine idle for 30s or so before switching off. Even better if you have a kill switch for the pump - use that - or pull the fuel pump fuse - then the engine will die when it uses up the fuel in the line. Then turn it off.

Vapour build up is something I never thought of and it does make sense. I had a similar problem on a previous TVR and this is very similar. The smell only starts several minutes after switching the engine off and is only noticeable in an enclosed area. I shall investigate further. Thanks Adam and everyone else for their suggestions.

Tony. TCB.