For the past 3 days running, I've noticed a fuel smell within the first mile or so after cold start. I pull over, open the hood and smell a faint but distinctive raw fuel smell from the left side of the engine bay. It's stronger in the front around the coolant reservoir. I do not smell it at all on the right side. After a few minutes it seems to fade and I don't smell it for the rest of the day.

I can't identify any wetness that might indicate dripping gasoline and it doesn't recur at all after a warm start.

Otherwise, the car runs beautifully.

I typically warm up the car for a few minutes before putting a load on the engine. I know running the car right away without a warm up is in vogue these days but I'm old fashioned that way. I do typically turn the key to On for about 10 seconds before starting the (cold) engine because I find (or imagine) the engine catches sooner that way. I do have the cap mod installed for the cold-to-warm transition.

Any tips on what I should be looking for or what might be causing this? This is on my series 3, by the way.

Thanks in advance,
Rhett

 

Hi Rhett,

Raw fuel smell not good, but....

There are no fuel related lines on the left / exhaust side.

Lines meet up aft and run along right side of car up to inlet part of engine.

Even the emissions canister is tucked up in the right side front wing.

Air con and smog pump (if unfortunate enough to have one fitted) are on the left, but they won't smell of fuel.

Fuel possibly running along front cross member, but you would probably see that outright.

Go figure?? Not much help, sorry.

In regards to turning key on, do you mean 1st position 'auxiliary' or 2nd position 'ignition'?

Auxiliary turns on electrics so OK, fuel pump builds pressure, etc.

Ignition powers the coil. All you are doing if this is the case is fry the coil and shorten its' life. Not so good.

Cheers,

Nigel

 

Me again,

I forgot to add..

When was the last time the fuel injection hose clamps were checked?

The smell may be captured under the bonnet and appear to come from somewhere else.

Just grab a medium sized flat head screwdriver and tweak each clamp that you can find.

Don't over tighten as you don't want to tear a hose, but you probably will find some clamps will take up an 1/8 to 1/4 turn.

While you're at it, tweak all the other clamps - water, AFM.

Preventative maintenance is always cheaper I find.

 

At least in LHD, the main fuel line coming from the tanks does enter the engine bay on the left side. It is routed to the fuel cooler (adjacent to the a/c compressor just ahead of the exhaust manifolds) then around the front of the head to the fuel rail. You could have a leak in these pipes, hoses or their connections.

I recently found a small leak at the hose between the rail and the cold start injector that was leaving a small amount of fuel behind on the intake only at start. A tiny amount but a strong smell. Tightening the hose clamp solved it. However, that is on the right side of the engine.

Hope you find the cause of the smell soon. Fuel leaks are no good :-)

 

@Rhett

Check the clamps on the 2" fuel hose at the front of the engine....... just underneath the oil breather......

If that hose leaks or drips, the fuel ends up getting mixed with the build up of oil and stuff on the front of the engine, so it's less noticeable than if one of the fuel injector clamps/hoses is leaking and you get fuel pooling on the inlet manifold.

Start the car from cold with the hood up, let it idle and watch all the hoses...... especially the one at the front of the engine.

I assume it's getting colder in Marin these days ? If its really cold you can have case where the joints are not completely sealing, but as soon as you get a little bit if heat coming on, they seal up again

 

Yeah, there is a fuel line on the left side of my LHD car.


I believe in "double clamping" critical rubber hoses.
The worm drive clamps have a "loose" spot. so,
I space them with the screws at 180 degrees apart.
And, I use a socket to tighten them, not a mere
screw driver. But, with care, it can be over done.


Once lived in nearby Mill Valley. A pleasant memory for
me and my family....


Carl

 

Yes, the temps are dropping into the 40's at night and the days are slow to warm back up. Nothing like the rest of the country but cooler than it's been in awhile. I'll go check the hoses... Thanks.

 

I found it! Right behind the fan, which explains why it smells stronger on the left of the engine. Two righty-tighty turns later and the fuel isn't leaking anymore. I could keep tightening, though. Should I keep tightening until it won't?

 

Victory! Well done.

No, tight enough is tight enough. You don't want to cut into the rubber with the edges of the clamp.