Strong Smell Of Petrol When Driving

[Paul17764]

Any Forumers had the problem?

When driving only I get a strong smell of petrol with the sunroof or drivers window open.

Any ideas much appreciated

Regards Paul

[wiseraven]

There are two common causes for this:

1. The fuel breather hose is rotten. See the LEW page for a howto.

2. Your rubber gearshift gaiter is split/missing. There are two gaiters on the shifter, the outer leather one, and an inner rubber one. It's the inner one that stops the vapour entering. I don't think there's a howto on that.

The fact that yours is only noticeable when the sunroof/window is open usually suggests the second, because you need a through draught to draw the vapour into the cockpit from the gearshift.

Phil

[CNH]

Probably comming in from the seat belt holes in the firewall or by a broken rubber shifter gaiter.

The fumes themselves are probably the result of several items that might be leaking.

1) The overhead crossover tubing that connects the twin tanks. This a known problem as the tubing disintergrates. (yellow hose syndrome). Hidden under the rear hatch gutters and carpet piece above the rear window.

2) Faulty one way check valve that is located near the intake cam gear. Looks like a small round disc in line between the intake side of the head and charcoal canister. When this fails it will allow intake fumes to blow back through the evaporative system instead of only allowing gas evaporation from tanks to be sucked and burned by the engine.

3) Fresh air intake and roll over valve located under right rear hatch gutter has fallen apart. The hose and plastic T's are the same type used on the crossover tube and is known to disintergrate. If the tubes are broken it is a direct connection to the filler pipe that connects and are in between the tanks and filler opening. It is possible when filling up petrol to spill fuel into the area behind the tank covers. Also the same is possible when doing aggresive manuvers as some fuel might splash up the filler necks and the hose as the vent hose has a tendancy to break at the this point.

4) leaking fuel tanks.

All these will allow fumes in the engine compartment. The vacumm created by the open window or sunroof will suck the fumes in to the cabin.

Edited April 12, 2007 by CNH

[Tentenths]

As Phil says, evidence points towards rubber gaiter. One of the jobs on our 'to do' list too (having already eliminated the 'split breather hose' syndrome).

Don't think anyone's written up a 'how to do' but I do know that Martynv (for one) has replaced the gaiter on his Esprit fairly recently. If he doesn't see this post I'm sure he wouldn't mind a PM asking for a few pointers.

[s4s]

In my case, injectors O-ring.

[martynv]

As Phil says, evidence points towards rubber gaiter. One of the jobs on our 'to do' list too (having already eliminated the 'split breather hose' syndrome).

Don't think anyone's written up a 'how to do' but I do know that Martynv (for one) has replaced the gaiter on his Esprit fairly recently. If he doesn't see this post I'm sure he wouldn't mind a PM asking for a few pointers.

James,

I did the gaiter last week and have taken plenty of pictures. I hope to do a LEW guide for it, although most is covered by the guide on changing the gear knob to a GT3 / Sport 350 one. The main trick is getting the gaiter over the lift tube, which looks to be impossible at first sight as the hole in the top is around 3/8" and the top of the lift tube is 1" plus . In the end I put the lift tube upright on the edge of the bench with the roll pins hanging over the edge and then spread a liberal quantity of Fairy Washing Up liquid inside the gaiter and finally pulled the gaiter down over the lift tube, which in the end slid over surprisingly easily :yes .

Martyn

[lemoncurd]

Not certain that this was the cause, but I used to get a similar fuel smell in the car while I had a dump valve installed on the car. I have taken it off for the moment because of insurance issues, and haven't noticed the smell recently - Haven't re connected the dump valve to confirm this though...

Ben

Edited April 12, 2007 by lemoncurd

[Paul17764]

Not certain that this was the cause, but I used to get a similar fuel smell in the car while I had a dump valve installed on the car. I have taken it off for the moment because of insurance issues, and haven't noticed the smell recently - Haven't re connected the dump valve to confirm this though...

Ben

Well a BIG Thank You to you all for you assistance, Will look into all of the above.....

Thanks Again Regards Paul

[Riddlemr2]

After doing some investigation, I think the rusty fuel tank problem is more common than is implied by the fact file, LEW, etc...The best way to tell is to open the trunk and have a big sniff near the battery and the power antenna. I learned the hard way that when buying an Esprit, not all fuel smells can be explained away by the fuel vent hose problem, though that is the most common cause. Good luck!

[martynv]

Well after replacing the gear shift gaiter as noted a few posts back, I thought I'd cured the smell I was getting inside my SE. However the smell came back with a vengance and after some investigation and removing the access panel on the right hand side of the engine bay (the bit with the carpet stuck to it in the rear window) I found the small length of "yellow hose" that connects the right hand filler neck vent to the roll-over valve had cracked almost all the way through in several places . The smell itself seems to come in via the seat belt hole on the bulkhead behind the drivers seat. I've taped it up for the time being, but my question now is do I replace it with the original Lotus polyurethane tube or should I just use conventional black petrol pipe ?. Any suggestions welcome.

Martyn

[lotus4s]

Any fuel hose if the correct size will work just fine.

[martynv]

Any fuel hose if the correct size will work just fine.

Thanks Jim, I thought that was probably the case. I was just wondering if Lotus had some reason for using this type of hose, I guess they just had a few hundred meters of it lying around .

Martyn

[esprits4de]

Well all symptoms described must be also applicable while the car is standing still with engine running.

In mine it does not smell. When I am driving though, that is especially when decellerating, a strong smell is noted.

I gues that is the resume from tuning the engine up so much, pouring the fuel into the engine bucketwise.

[martynv]

Well I changed the offending pipe at the weekend here's what it looked like

You can clearly see it's cracked half the way through in places. I also found this little chap about 2" from the roll over valve end of the pipe

Obviously some sort of restrictor, worth bearing in mind if your replacing this bit of pipe in case you accidentaly throw it away. I managed to shove him up the new pipe with the help of a 1/4" socket extension

The really bad smell of petrol has now gone but there still seems to be a more mild smell getting in somewhere, so I guess more searching is required !

Martyn

[toyroom]

I have spent over a year trying to eradicate a fuel smell. The problem is pressing as the car lives in an integral garage next to the kitchen and food is beginning to taste of petrol ! We replaced the right side fuel rail last week to no avail ( The service port was leaking so the job was worth doing, but the smell remains. We replaced the balance pipe between the tanks ( two rubber bits and a steel tube) But again, no luck. The fuel system holds pressure well and the car has been fitted with an EGR valve.

There is no doubt at all that the smell is " loudest" in the viscinity of the metal part of the lower balance pipe with the smell then travelling up the front of the engine and also to the left rear wheelarch. Bizarrely, it appears in the front wheelarches as well ! This supports the idea that the smell starts somewhere just in front of the crankshaft and then convects up the front of the engine and along the inside of the backbone. The valley between the cylinders (It's a V8) has no smell at all and nor do the injector rails or service port. There is no smell behind the trim panels which sit above the tanks.

Question is: If the smell is comming (or seeming to be coming) from the central pipe of the balancing hose and pipe, but this has been replaced in its entirety with new jubilee clips etc. and no sign of any petrol stains: Where on Earth is the leak !!??

Thanks for any ideas. Meanwhile, I will investigate the upper balance pipe. Where exactly does it lie, height-wise ??

Thanks again

[Tentenths]

Meanwhile, I will investigate the upper balance pipe. Where exactly does it lie, height-wise ??

I assume you're referring to the flexible breather hose thingy, John?

If so, this should point you in the right direction.

[toyroom]

Yes. Thanks. I 5think it's either this or the right tank

[DarrenWalesUK]

I had a strong smell of petrol and followed the HOW TO DO to find out that it was the breather pipe between the 2 tanks, I had a job to get a internal braided 10mm pipe , When i found some i had to buy a reel. Simple job to do and worked a treat !. I have enough for another 2 esprits if anybopdy wants some FREE of charge , Just drop me a PM . CHEERS DARREN

[davevr6car]

Any Forumers had the problem?

When driving only I get a strong smell of petrol with the sunroof or drivers window open.

Any ideas much appreciated

Regards Paul

Hi Paul,

I had the same problem and it drove me mad.

The smell was very strong with the drivers window down and got worse under hard acceleration.

I checked everything but to no avail and gave up.

About six months later while looking at something else I noticed the small clear pipe going to the carbon canister was cracked.

Replaced the pipe and cured the petrol smell.

cheers

Dave

[matk]

Darren

I'll have some off you, but I feel I should pay something. If you don't want it I'll make a contribution to Bibs. Can you let me know here or by PM?

[Paul93Lotus]

All that clear tubing should be replaced if possible....the evaporative emissions, and the venting line between tanks. It WILL crack and break on ALL cars at some point. It just can't cope with the vapors.

I just worked on this yesterday and the prior owner replaced the crossover vent line up to the plastic elbows, but left the rest of the old orange tubing. Guess what...It broke completely at the vent, and cracked half way up to the rollover tube.

If you're in there you're stupid if you don't replace it all, becuase you'll be in there again for what you don't replace.

Edited September 16, 2007 by Paul93Lotus

[Kirk Adamson]

hi. i have the same problem. 1989 turbo carb model. there seems to be two pipes running across the top. i can see one goes back to the drivers side tank . but cant see where the other goes .? . mine just fell to bits as soon as i touched them so at a bit of a loss where the other pipe goes or exits etc ? the passanger side has the plastic t piece but nothing on the drivers side to say where other pipe goes . help please ;-)

[top-plumber]

I think you will find that it goes to the roll over valve and then down to the charcoal canister. The whole pipe should be replaced not repaired. Take a look in the service and maintenance manual for the schematic.

Good luck

[Jacques]

there is a "t" in one side for the tilt over shut off valve which sits behind a c-pillar.

 

Kind regards,

Jacques.

[top-plumber]

There is also a ristricter in that pipe it looks like a carburettor jet and should not be left out.