Help With Petrol Problem, Please Please!

[Donna And Nelly]

Hi. We have a 1998 Previa R reg. Its been a fantastic car, we love it. Have had it 7 years now with no problems. Its been amazing!

But its developed a nasty petrol smell.

When driving it you can smell it from inside the car. From outside the car you can smell it in the back passenger foot well area (or just standing at the back of the sliding door)

Its been checked over by a garage who said theres no obvious leaks. We've had a local mechanic out who also has checked over it and found nothing.

My husband has had all the inside covers off, wheel arch cover off, traced the pipes as far as he can and no leak, but the car still smells.

Its still running fantastic, if anything slightly more economical than usual, still as quick if you kick it down.

The only difference is when you put petrol in, it used to make a gushing noise like it was sucking air in, it doesn't do that anymore.

Were supposed to be going on holiday in it next week but the thought of loading it up with us and the kids is rather frightening. So if you have any idea on what to do next or check then please please let me know.

Thanks, Donna. :(

[Tardis]

I don't have any experience of this on the Previa but from your description of the location of the smell and the pipe tracing done so far, it sounds like a problem at or near the fuel tank. Normally the tank has a pipe to the fuel filler, and another hole for the fuel pump and gauge sender, the seals at these holes can deteriorate and then leak.

The best answer (and unfortunately not easiest or cheapest) is to drop the fuel tank from the car and check it all over.

Good luck.

[JackD]

I had this problem on my N-reg Previa. Mine was traced to corrosion of the metal pipes between the fuel filler and the petrol tank. It's apparently a known problem with Previas, and means replacing the metal pipes. It cost me £100 (parts & labour) and cured the problem.

The mechanic showed me the old pipes and they were paper-thin in places with pinholes giving rise to the smell and small leaks when topped right up. He also said that the Toyota storesman knew all about this problem, knew which bits to supply and even had them in stock!

Hope this helps.

John D

[Pat2u]

I had this problem on my N-reg Previa. Mine was traced to corrosion of the metal pipes between the fuel filler and the petrol tank. It's apparently a known problem with Previas, and means replacing the metal pipes. It cost me £100 (parts & labour) and cured the problem.

The mechanic showed me the old pipes and they were paper-thin in places with pinholes giving rise to the smell and small leaks when topped right up. He also said that the Toyota storesman knew all about this problem, knew which bits to supply and even had them in stock!

Hope this helps.

John D

Sounds about right John, i had a simular problem on a rover sdi caused by the rear wheels washing rainwater on to the filler pipe in turn corroding the down pipe from the fuel filler cap, the strong smell of petrol was very noticable inside the car due to the vacume created within the tank whilst driving, had i filled the car up to max at anytime the problem would have been noticed earlier due to loss of petrol showing on the forecourt whilst rising up the kneck of the filler pipe.

I was lucky the filler pipe was seperated by a short rubber tube section leading to the tank and the only replacement was a new metal section from filler cap to the first section leading to the rubber section, i have no idea if the previa down pipe has a simular section however i would take a look.

[miti-babe]

Donna

The problem is likely due to a fault with the 3-way valve on the carbon-cannister under the front passenger seat. It is there to "store" fuel fumes from the tank vents... When it gets old and deteriorates it can "clog up" this causes back-pressure in the fuel tank... and fumes...

The filler pipe has a breather too, if it deteriorates at the same time as the cannister valve, you'll get fumes in the cabin - exactly as you've described...

The cannister on my '91 2.4GL was cream-crackered when I bought the car - £145 plus VAT..!! I cut the breather and wedged an M8 bolt into it - That was 4 years ago... Recently we started to get fumes in the cabin... I took the fuel filler cap off and tried driving without... No fumes in the cabin, but it does still smell of fuel around the filler, after you've stopped...

My car ain't worth spending all the cash on a new cannister and removing the tank to replace all the seals/joints, but yours may be... I'm going to drill a hole thru the filler cap to vent the fumes and won't be pulling the tank unless it starts to leak (won't be long now I reckon...)

Problems like these are largely due to changes in modern fuels - there is a lot of alcohol in modern fuels (to increase the Octane rating and prevent pre-ignition) The pipes, seals, etc that were fitted as new are not as resistant to these changes and, sadly, deteriorate... I have 5 Japanes motorcycles from the 1980's... ALL of them suffer with leaking carburettors/tank seals and pipework - 3 different manufacturers... Can't be a coincidence can it..?

Miti

BTW: The filler inlet is about 18" above the tank - it'll only ever spill out (without a cap) if the Old Bus is on her side... I'll worry about that problem at the time... ;-)