'95 Camry Chronic Fuel Leakage

Our '95 four cylinder sedan was a great, trouble-free car for many
years, until it developed a modest fuel leak. Little did we know how
much of a problem this would be! First the dealer replaced the gas tank;
the leak stopped, only to return a short time later. With no apologies
or discount, the dealer then said it was a rusty fill pipe, and replaced
that, with the same result: the leak stopped for a while, then returned.

I'm sure that some of you have guessed what comes next. Next time
around we were told that it was "probably" the evap vapor recovery
canister leaking gas. The price for the part was so high - about $400
for the part alone - that I went to to Ebay and got one for $100 from a
reputable seller. The part *looked* authentic, and when installed the
problem again went away, this time for about a year. Last month the leak
started again, and the local shop said it was the canister O-rings, and
replaced those. Yes, you guessed it, the problem came back again last
week. The local shop said it was the canister leaking. The problem
occurs either mainly or only after filling the tank completely,
something we obviously try to avoid doing if possible. The only other
clue I can offer is that the fuel gauge became inaccurate after the tank
was replaced, and now reads a little high. This makes it harder to
*almost* fill the tank.

The car has 190k miles on it, but we hate to junk it, because both
the engine and transmission are still tight and smooth, the body is
still fine, and we had timing belt/water pump/CV joints/brakes done last
Fall. The new brakes are the first ones the car has had that actually
felt strong and smooth! The car still averages 30+ mpg per tank. So,
does anyone have a a solution? I'm cross-posting this to the Volvo
newsgroup because there are several clandestine Camry owners there. ;-)

 

Oh, and we haven't gotten a Check Engine light at all. Just gasoline
fumes.

 

Can you tell exactly where it's leaking from? I've never worked on a
Camry, but the Toyotas I've dealt with have been quite good overall.
There's only so many places fuel can leak from, and it's usually not too
hard to see where.

 

Initially from the rear. After the fill pipe was replaced the leak
next appeared under the left front of the car, roughly where the evap
canister is buried in the engine compartment. I don't doubt that the gas
is coming from the canister; what I suspect is that there is another
underlying cause that isn't being addressed. The 'replace everything
until it stops' approach of the dealer has been replaced by the 'just
fix what's obviously wrong' approach of our local mechanic. My housemate
thinks they somehow mis-installed the filler pipe and that is causing
the canister to flood with gas. Maybe, I don't know...

 

Now for a dumb question - has it been 'over-filled' with fuel at any
stage? Even once?

Cheers,
Andy.

 

That depends on how you define "overfilled." It's gone slightly past
the pump auto shutoff, but not to the overflow point. That was before
the first canister was replaced.

 

Well, that would be a reasonable definition

OIC. Probably irrelevant then.

Are you able to get a visual/easy removal on the hoses at the cannister
end? There shouldn't really be any liquid petrol anywhere near it.

Cheers,
Andy. (Reading/responding from the Volvo group, so please don't trim
followups)

 

I think the canister is buried - I can't even see it from above. To
clarify: I think there was one overfill from a malfunctioning gas pump
before the first canister failed - probably from the raw gas. After
that, I would occasionally check the fuel economy by rounding it up to
the nearest nickel after the shutoff. I' m talking about *two or three
cents* worth of gas, here. That shouldn't be enough to damage a canister
under normal circumstances...right?

 

Sounds about right.

Correct. That much wouldn't have been enough to fill the vapour line
with raw fuel.

Anyway, apologies for more questions, but I'm pretty sure I missed the
start of the thread - anyway,

Mention was made of the entire filler pipe being replaced - this was
definitely replaced with the correct part for the car, yes?

I'm thinking there's some kind of strange vacuum condition pulling gas
from the tank to the charcoal cannister. Stuffed if I know how that
would happen though. Hoses hooked up arse-about on the cannister is a
possibility (a long shot, but I've learnt to never rule anything out).

If it were me, I'd pull the vent hose that runs from the tank to the
cannister at the tank end, start the car and run it under various
throttle conditions to try and feel for any particularly strong vacuum.

Let us know how you go.

Cheers,
Andy.

 

Sounds like this might be one of those 'drop it off the workshop and
tell them to just fix it' type jobs.

I'm not all that familiar with Camrys - do you get any 'check engine'
light or codes on the dash whilst driving before the leaking starts?

I'm inclined to agree.

I found this online which outlines the system pretty well:

http://www.autoshop101.com/forms/h62.pdf

Something (someone) blocking off the bottom of the canister where it
draws fresh air (perhaps in a failed attempt to stop the leak
previously?) could (and I'm taking a massive, massive stab in the dark
here) potentially cause unusual amounts of vacuum on the fuel tank from
the canister.

Realistically, the whole evaporative control system will need to be
looked at to get a proper diagnosis. Components could be acting up
causing strange behaviour. Someone who knows these cars needs to double
check that the hoses are connected to the right ports to/from the
canister to the thermal vac valve, the purge point and the fuel tank.

A '95 Camry? Hell, it's probably only just run in!

Cheers and good luck,
Andy.

 

The new fill pipe was installed by a Toyota dealer. I can't work on
it myself (poor health) but I'll see if I can get the local mechanics to
do that check when they install the second new canister. My housemate
thinks the dealer screwed up the fill pipe installation...

Anyway, two questions: if we never fill the tank completely, can it
still pull gas to the canister? And is there a way to bypass the
canister after it's inspected? I'm a firm believer in emissions
controls, but this one isn't working properly. It would be nice if the
car could get through one more Winter, as it drives better than some of
the newer ones out there.

 

I basically agree with you, but I don't have a lot of confidence in
the local mechanics - or the dealers! - to correctly diagnose the
problem. We will probably have the new canister installed and then
carefully not fill the tank to the top as we (hopefully) get another
Winter out of the car.

 

You looking at at least an $800 bill for the canister install with labor? Do
you support questionable emissions standards THAT strongly?

 

$285 for the canister, via an online parts retailer, about $125 for
the labor. Now what is it about containing unburned gasoline vapor that
you think is a bad idea? If you say "This particular implementation of a
vapor recovery system" then I'll agree. If you say "Recovering the
vapor", then we have nothing to discuss...

 

There are NO vehicle emission inspections here in Alberta. Rest assured, IF
my canister or associated parts every fail, they will be left that way. Far,
far more air pollution is caused by cattle farting methane and by volcanic
eruptions.

 

Yes, I agree that volcanic eruptions are even worse than
head-in-the-sand car owners. ;-)

 

Or "more money than brains" ones, too.

 

Probably a Honda.

 

I should have specified *large* volcanic eruptions as being worse
than dunderhead car owners.

My other car is *not* a Rolls.