| Author |
Message |
Codifus
Guest
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 Posted:
Wed Nov 02, 2005 9:20 pm Post subject:
Re: Cheating gas station? True tank capacity? |
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NoNoBadDog! wrote:
| Quote: | "Pszemol" <Pszemol@PolBox.com> wrote in message
news:dk8ka3.94.1@poczta.onet.pl...
"NoNoBadDog!" <no_@spam_verizon.net> wrote in message
news:9jU9f.1492$W%2.126@trnddc06...
In addition, letting the tank go to nearly empty causes sediments
that would normally be at the bottom of the tank to be introduced into
the fuel system, clogging filters and making the pump work harder.
Have you guys ever cut the tank open to see these "sediments"?
I have heard about these sediments but I have never had a chance
to see them... ;-)
best advice is to never let the fuel tank get below 1/4.
I would guess the fuel is bouncing left and right there on every turn
stirring "sediments" from the bottom no matter if it is 1/4 or 1/16 full.
The detergent that is included in most modern gasolines keeps the sediment
from staying suspended in the gasoline for any length of time (in addition
to helping keep the lines clean). In most driving situations, the sediments
are not a problem. only when the gas gets very low and they have nowhere
else to go do they get sucked into the system.
Bobby
How bad a problem can this be? The feul pump has a strainer at the |
receiving end and feul filter at the injector end. It looks like the
system is well protected.
Just wondering.
CD
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E Meyer
Guest
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| Posted:
Wed Nov 02, 2005 10:09 pm Post subject:
Re: Cheating gas station? True tank capacity? |
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On 11/2/05 9:20 AM, in article PO4af.38699$rE2.32027@fe10.lga, "Codifus"
<codifus@optonline.net> wrote:
| Quote: | NoNoBadDog! wrote:
"Pszemol" <Pszemol@PolBox.com> wrote in message
news:dk8ka3.94.1@poczta.onet.pl...
"NoNoBadDog!" <no_@spam_verizon.net> wrote in message
news:9jU9f.1492$W%2.126@trnddc06...
In addition, letting the tank go to nearly empty causes sediments
that would normally be at the bottom of the tank to be introduced into
the fuel system, clogging filters and making the pump work harder.
Have you guys ever cut the tank open to see these "sediments"?
I have heard about these sediments but I have never had a chance
to see them... ;-)
best advice is to never let the fuel tank get below 1/4.
I would guess the fuel is bouncing left and right there on every turn
stirring "sediments" from the bottom no matter if it is 1/4 or 1/16 full.
The detergent that is included in most modern gasolines keeps the sediment
from staying suspended in the gasoline for any length of time (in addition
to helping keep the lines clean). In most driving situations, the sediments
are not a problem. only when the gas gets very low and they have nowhere
else to go do they get sucked into the system.
Bobby
How bad a problem can this be? The feul pump has a strainer at the
receiving end and feul filter at the injector end. It looks like the
system is well protected.
Just wondering.
CD
|
I always run them down to within 1 or 2 gallons remaining. I have only
experienced sediment problems once (driving for 40 years now) and then it
was with a diesel Oldsmobile. The filter screen at the inlet in the tank
clogged and the car wouldn't run because nothing got through. I think you
are correct that the filters will prevent it from harming anything. |
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NoNoBadDog!
Guest
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| Posted:
Thu Nov 03, 2005 1:42 am Post subject:
Re: Cheating gas station? True tank capacity? |
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"Codifus" <codifus@optonline.net> wrote in message
news:PO4af.38699$rE2.32027@fe10.lga...
| Quote: | NoNoBadDog! wrote:
"Pszemol" <Pszemol@PolBox.com> wrote in message
news:dk8ka3.94.1@poczta.onet.pl...
"NoNoBadDog!" <no_@spam_verizon.net> wrote in message
news:9jU9f.1492$W%2.126@trnddc06...
In addition, letting the tank go to nearly empty causes sediments
that would normally be at the bottom of the tank to be introduced into
the fuel system, clogging filters and making the pump work harder.
Have you guys ever cut the tank open to see these "sediments"?
I have heard about these sediments but I have never had a chance
to see them... ;-)
best advice is to never let the fuel tank get below 1/4.
I would guess the fuel is bouncing left and right there on every turn
stirring "sediments" from the bottom no matter if it is 1/4 or 1/16 full.
The detergent that is included in most modern gasolines keeps the
sediment from staying suspended in the gasoline for any length of time
(in addition to helping keep the lines clean). In most driving
situations, the sediments are not a problem. only when the gas gets very
low and they have nowhere else to go do they get sucked into the system.
Bobby
How bad a problem can this be? The feul pump has a strainer at the
receiving end and feul filter at the injector end. It looks like the
system is well protected.
Just wondering.
CD
|
Please re-read my post. The problem is worst when letting the tank become
nearly empty.
If the tank is kept above being "nearly empty", then the sediments rarely if
ever cause any problems.
When changing defective senders, or replacing damaged tanks, I have seen
instances where there were alarming amounts of rust, ketones and varnish at
the bottom of the tank. If you read my post, you'll see I stated that under
normal driving (i.e. never letting the tank approach empty", it's not a
problem. I was responding to someone who claims to always let their tank
get nearly empty, which causes the fuel pump to work harder and increases
the chances of damage to the fuel system from the accumulated sediments. If
you have ever looked at a gas tank, most have little valley like
depressions stamped into the metal. This is for the accumulation of the
sediments.
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Andy Champ
Guest
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| Posted:
Thu Nov 03, 2005 6:27 am Post subject:
Re: Cheating gas station? True tank capacity? |
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NoNoBadDog! wrote:
| Quote: | Topping off has no negative impact whatsoever. Continually letting the tank
go below 1/4 does have a negative impact...the fuel pump must work much
harder at low fuel levels to develop sufficient vacuum to keep gas flowing
to the engine. In addition, letting the tank go to nearly empty causes
sediments that would normally be at the bottom of the tank to be introduced
into the fuel system, clogging filters and making the pump work harder.
best advice is to never let the fuel tank get below 1/4.
Bobby
|
Well I always did that for the 100k as well... I think that's a myth TBH.
Andy |
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NoNoBadDog!
Guest
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| Posted:
Thu Nov 03, 2005 8:46 am Post subject:
Re: Cheating gas station? True tank capacity? |
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"Andy Champ" <no.way@nospam.com> wrote in message
news:7d6dndPx3dLS1vTenZ2dnUVZ8tydnZ2d@pipex.net...
| Quote: | NoNoBadDog! wrote:
Topping off has no negative impact whatsoever. Continually letting the
tank go below 1/4 does have a negative impact...the fuel pump must work
much harder at low fuel levels to develop sufficient vacuum to keep gas
flowing to the engine. In addition, letting the tank go to nearly empty
causes sediments that would normally be at the bottom of the tank to be
introduced into the fuel system, clogging filters and making the pump
work harder. best advice is to never let the fuel tank get below 1/4.
Bobby
Well I always did that for the 100k as well... I think that's a myth TBH.
Andy
|
Believe what you will...it's a free country. Allowing a tank to approach
empty stresses the fuel pump unnecessarily, period. No need to make the
system work harder than it has to. Besides, why risk running out of gas?
Bobby |
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Pszemol
Guest
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| Posted:
Thu Nov 03, 2005 9:14 am Post subject:
Re: Cheating gas station? True tank capacity? |
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"Andy Champ" <no.way@nospam.com> wrote in message news:7d6dndPx3dLS1vTenZ2dnUVZ8tydnZ2d@pipex.net...
| Quote: | Topping off has no negative impact whatsoever. Continually letting the tank
go below 1/4 does have a negative impact...the fuel pump must work much
harder at low fuel levels to develop sufficient vacuum to keep gas flowing
to the engine. In addition, letting the tank go to nearly empty causes
sediments that would normally be at the bottom of the tank to be introduced
into the fuel system, clogging filters and making the pump work harder.
best advice is to never let the fuel tank get below 1/4.
Well I always did that for the 100k as well... I think that's a myth TBH.
|
Same here. I always refuel when my warning indicator is on for a while.
And I always top it off to the cap - I just hate wasting my time on taking fuel.
Never had any trouble with the fuel pump in both of my vehicles...
It could be some of vehicles are better in their pumps and some worse.
I have toyota camry '95 purchased in 98 at 47kmiles - now it has 192k.
I also have nissan sentra '94 purchased in 02 at 87kmiles - now it has 140k.
Had two cars before 1998 in Europe, with significant millage on them too.
Never had problems with fuel pumps, fuel injectors nor gunk in the fuel tank.
Sounds like the myth based on the anegdotal evidence. |
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Codifus
Guest
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| Posted:
Thu Nov 03, 2005 7:45 pm Post subject:
Re: Cheating gas station? True tank capacity? |
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Pszemol wrote:
| Quote: | "Andy Champ" <no.way@nospam.com> wrote in message
news:7d6dndPx3dLS1vTenZ2dnUVZ8tydnZ2d@pipex.net...
Topping off has no negative impact whatsoever. Continually letting
the tank go below 1/4 does have a negative impact...the fuel pump
must work much harder at low fuel levels to develop sufficient vacuum
to keep gas flowing to the engine. In addition, letting the tank go
to nearly empty causes sediments that would normally be at the bottom
of the tank to be introduced into the fuel system, clogging filters
and making the pump work harder. best advice is to never let the fuel
tank get below 1/4.
Well I always did that for the 100k as well... I think that's a myth
TBH.
Same here. I always refuel when my warning indicator is on for a while.
And I always top it off to the cap - I just hate wasting my time on
taking fuel.
Never had any trouble with the fuel pump in both of my vehicles...
It could be some of vehicles are better in their pumps and some worse.
I have toyota camry '95 purchased in 98 at 47kmiles - now it has 192k.
I also have nissan sentra '94 purchased in 02 at 87kmiles - now it has
140k.
Had two cars before 1998 in Europe, with significant millage on them too.
Never had problems with fuel pumps, fuel injectors nor gunk in the fuel
tank.
Sounds like the myth based on the anegdotal evidence.
I would tend to agree. I've also noticed that feul pumps have gotten |
much smaller and more powerful. The feul pump in the 96 Altima is twice
the size of the feul pump in the 98 Altima yet they both have drive same
engine, more powerfull in the 98 version of course.
CD |
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Jason Outman
Guest
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| Posted:
Fri Nov 04, 2005 1:49 am Post subject:
Re: Cheating gas station? True tank capacity? |
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"Codifus" <codifus@optonline.net> wrote in message
news:awoaf.8074$ex4.7776@fe08.lga...
| Quote: | Pszemol wrote:
"Andy Champ" <no.way@nospam.com> wrote in message
news:7d6dndPx3dLS1vTenZ2dnUVZ8tydnZ2d@pipex.net...
Topping off has no negative impact whatsoever. Continually letting the
tank go below 1/4 does have a negative impact...the fuel pump must work
much harder at low fuel levels to develop sufficient vacuum to keep gas
flowing to the engine. In addition, letting the tank go to nearly
empty causes sediments that would normally be at the bottom of the tank
to be introduced into the fuel system, clogging filters and making the
pump work harder. best advice is to never let the fuel tank get below
1/4.
Well I always did that for the 100k as well... I think that's a myth
TBH.
Same here. I always refuel when my warning indicator is on for a while.
And I always top it off to the cap - I just hate wasting my time on
taking fuel.
Never had any trouble with the fuel pump in both of my vehicles...
It could be some of vehicles are better in their pumps and some worse.
I have toyota camry '95 purchased in 98 at 47kmiles - now it has 192k.
I also have nissan sentra '94 purchased in 02 at 87kmiles - now it has
140k.
Had two cars before 1998 in Europe, with significant millage on them too.
Never had problems with fuel pumps, fuel injectors nor gunk in the fuel
tank.
Sounds like the myth based on the anegdotal evidence.
I would tend to agree. I've also noticed that feul pumps have gotten much
smaller and more powerful. The feul pump in the 96 Altima is twice the
size of the feul pump in the 98 Altima yet they both have drive same
engine, more powerfull in the 98 version of course.
CD
|
The issue is only on vehicles that have the pump located in the tank. It
has nothing to do with working harder, it has to do with heat dissipation.
Most in-tank fuel pumps are designed to use the fuel surrounding the pump to
cool it down, as opposed to ones mounted outside the tank which uses the
fuel flowing through the pump to cool it. The number one killer of any
electric motor is overheating. |
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Codifus
Guest
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| Posted:
Fri Nov 04, 2005 5:55 am Post subject:
Re: Cheating gas station? True tank capacity? |
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Jason Outman wrote:
| Quote: | "Codifus" <codifus@optonline.net> wrote in message
news:awoaf.8074$ex4.7776@fe08.lga...
Pszemol wrote:
"Andy Champ" <no.way@nospam.com> wrote in message
news:7d6dndPx3dLS1vTenZ2dnUVZ8tydnZ2d@pipex.net...
Topping off has no negative impact whatsoever. Continually letting the
tank go below 1/4 does have a negative impact...the fuel pump must work
much harder at low fuel levels to develop sufficient vacuum to keep gas
flowing to the engine. In addition, letting the tank go to nearly
empty causes sediments that would normally be at the bottom of the tank
to be introduced into the fuel system, clogging filters and making the
pump work harder. best advice is to never let the fuel tank get below
1/4.
Well I always did that for the 100k as well... I think that's a myth
TBH.
Same here. I always refuel when my warning indicator is on for a while.
And I always top it off to the cap - I just hate wasting my time on
taking fuel.
Never had any trouble with the fuel pump in both of my vehicles...
It could be some of vehicles are better in their pumps and some worse.
I have toyota camry '95 purchased in 98 at 47kmiles - now it has 192k.
I also have nissan sentra '94 purchased in 02 at 87kmiles - now it has
140k.
Had two cars before 1998 in Europe, with significant millage on them too.
Never had problems with fuel pumps, fuel injectors nor gunk in the fuel
tank.
Sounds like the myth based on the anegdotal evidence.
I would tend to agree. I've also noticed that feul pumps have gotten much
smaller and more powerful. The feul pump in the 96 Altima is twice the
size of the feul pump in the 98 Altima yet they both have drive same
engine, more powerfull in the 98 version of course.
CD
The issue is only on vehicles that have the pump located in the tank. It
has nothing to do with working harder, it has to do with heat dissipation.
Most in-tank fuel pumps are designed to use the fuel surrounding the pump to
cool it down, as opposed to ones mounted outside the tank which uses the
fuel flowing through the pump to cool it. The number one killer of any
electric motor is overheating.
Aren't all modern feul pumps inside the tank? I was under the impression |
that that was part of the evolution of the technology. External feul
pumps are from older cars, like drum brakes, carbureutors, etc.
I can understand and beleive the heat dissipation part, but it seems
that feul pumps have become so bullet proof that they can withstand
years and years of low-feul situations without going bust.
I have replaced 2 feul pumps in 2 cars, and I'm sure their failure was
due to severe lack of maintenance on the previous owner's part. My 99
Sentra felt like it had the original Nissan feul filter when the car was
new, and I bought it used at 94K miles! The car had absolutely no power
on the highway. I replaced the feul filter and a significant amout of
power came back. Replacing the feul pump, it hadn't died but I suspected
that it was dying due to un-even strange accelerative behavior, got rid
of the last of those strange quirks.
CD |
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Andy Champ
Guest
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| Posted:
Sat Nov 05, 2005 2:10 am Post subject:
Re: Cheating gas station? True tank capacity? |
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NoNoBadDog! wrote:
| Quote: | Well I always did that for the 100k as well... I think that's a myth TBH.
Andy
Believe what you will...it's a free country. Allowing a tank to approach
empty stresses the fuel pump unnecessarily, period. No need to make the
system work harder than it has to. Besides, why risk running out of gas?
Bobby
|
They say this is a free country too - but that's another matter.
I can't believe the extra head of fuel in the tank - it's what, a foot
high? - can make any difference. And I knew that I had another 50 miles
at least in the tank, I wasn't going to run out (petrol stations are
never that far apart, it's not like the gas stations in the middle of
Nevada). I also object to visiting the petrol station too often, it's
off my route and I reckon I waste 5 minutes every time I go there. This
minutes add up...
Jason might have a point about the cooling. That's far more likely than
the actual pressure difference.
Still - as neither of us have good data (as in, stats from hundreds of
cars) lets just agree to differ.
Andy |
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???
Guest
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| Posted:
Thu Nov 24, 2005 9:15 am Post subject:
Re: Cheating gas station? True tank capacity? |
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Sorry, I didn't mean filling the tank often is bad but putting the
extra gas after the gas pump has already stopped pumping.
On Wed, 23 Nov 2005 22:44:40 -0500, ??? <???@ibm.net> wrote:
| Quote: | Topping off is generally not a good idea environmentally. Much of the
extra fuel just evaporates.
On Tue, 01 Nov 2005 20:49:19 -0500, Codifus <codifus@optonline.net
wrote:
Pszemol wrote:
"Codifus" <codifus@optonline.net> wrote in message
news:hZQ9f.4976$ex4.2044@fe08.lga...
Well, I replaced the feul pump in my sentra and attached to it I found
a mechanism which I beleive is the low feul warning mechanism. It
seems to work just like the the plunger in a toilet bowl. This ball
with air in it floats above the gas. That floater is tied to a
somewhat flimsy metal rod which attaches to some sort of circuit. The
circuit apparently measures the swing of the rod. If you fill up with
too much gas the "floater" may be pushed too far, bending the flimsy
rod a little, and thus fmaking the mechanism lose its accuracy at
detecting low feul levels.
What you saw is the fuel gauge sensor, sometimes called a "sender unit".
The warning light is usually made as an addition to the fuel gauge: when
the electric current flowing through the variable resistor in the sending
unit and the gauge is large enough for the gauge to show near "empty"
the warning light will also go on.
Notice that when the tank is already full, the fuel is up to the ceiling of
the tank and the float does not have any room to go anywhere so it
stays submerged in fuel. It will not move until the fuel level drops...
You may have noticed how your gauge tends to stay on full for quite
a while after filling up. So I am pretty sure filling the hoses from
the filling cap down when you top-off would not change a thing...
That's what I saw. From my experience, I tend to over fill alot, and
slowly I noticed my previous Altima lose accuracy in detecting low
feul levels.
Your observation may be true, but the correlation between topping
off and diminishing fuel measuring accuracy totaly not existent...
What you probably see is the variable resistor in the sending unit
getting old and dirty, not conducting electric current like it used to
when it was brand new. That is all. I would not blame topping off.
Fair enough. I'll continue to top off with confidence then!
CD |
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???
Guest
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| Posted:
Thu Nov 24, 2005 9:15 am Post subject:
Re: Cheating gas station? True tank capacity? |
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Topping off is generally not a good idea environmentally. Much of the
extra fuel just evaporates.
On Tue, 01 Nov 2005 20:49:19 -0500, Codifus <codifus@optonline.net>
wrote:
| Quote: | Pszemol wrote:
"Codifus" <codifus@optonline.net> wrote in message
news:hZQ9f.4976$ex4.2044@fe08.lga...
Well, I replaced the feul pump in my sentra and attached to it I found
a mechanism which I beleive is the low feul warning mechanism. It
seems to work just like the the plunger in a toilet bowl. This ball
with air in it floats above the gas. That floater is tied to a
somewhat flimsy metal rod which attaches to some sort of circuit. The
circuit apparently measures the swing of the rod. If you fill up with
too much gas the "floater" may be pushed too far, bending the flimsy
rod a little, and thus fmaking the mechanism lose its accuracy at
detecting low feul levels.
What you saw is the fuel gauge sensor, sometimes called a "sender unit".
The warning light is usually made as an addition to the fuel gauge: when
the electric current flowing through the variable resistor in the sending
unit and the gauge is large enough for the gauge to show near "empty"
the warning light will also go on.
Notice that when the tank is already full, the fuel is up to the ceiling of
the tank and the float does not have any room to go anywhere so it
stays submerged in fuel. It will not move until the fuel level drops...
You may have noticed how your gauge tends to stay on full for quite
a while after filling up. So I am pretty sure filling the hoses from
the filling cap down when you top-off would not change a thing...
That's what I saw. From my experience, I tend to over fill alot, and
slowly I noticed my previous Altima lose accuracy in detecting low
feul levels.
Your observation may be true, but the correlation between topping
off and diminishing fuel measuring accuracy totaly not existent...
What you probably see is the variable resistor in the sending unit
getting old and dirty, not conducting electric current like it used to
when it was brand new. That is all. I would not blame topping off.
Fair enough. I'll continue to top off with confidence then!
CD |
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1mmg6cN7
Guest
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willshak
Guest
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| Posted:
Thu Nov 24, 2005 9:57 pm Post subject:
Re: Cheating gas station? True tank capacity? |
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On 11/23/2005 10:44 PM US(ET), ??? took fingers to keyboard, and typed
the following:
| Quote: | Topping off is generally not a good idea environmentally. Much of the
extra fuel just evaporates.
|
Today's gas caps are not vented as they were in the past. That's why the
Check Engine light can come on when the caps are not tight. Even if they
were vented, are you saying that the gas in a few square inches of
surface area, like in the filler neck, is likely to evaporate more than
if the surface area of the gas was as wide and long as the gas tank?
That goes against what little I know of physics.
| Quote: | On Tue, 01 Nov 2005 20:49:19 -0500, Codifus <codifus@optonline.net
wrote:
Pszemol wrote:
"Codifus" <codifus@optonline.net> wrote in message
news:hZQ9f.4976$ex4.2044@fe08.lga...
Well, I replaced the feul pump in my sentra and attached to it I found
a mechanism which I beleive is the low feul warning mechanism. It
seems to work just like the the plunger in a toilet bowl. This ball
with air in it floats above the gas. That floater is tied to a
somewhat flimsy metal rod which attaches to some sort of circuit. The
circuit apparently measures the swing of the rod. If you fill up with
too much gas the "floater" may be pushed too far, bending the flimsy
rod a little, and thus fmaking the mechanism lose its accuracy at
detecting low feul levels.
What you saw is the fuel gauge sensor, sometimes called a "sender unit".
The warning light is usually made as an addition to the fuel gauge: when
the electric current flowing through the variable resistor in the sending
unit and the gauge is large enough for the gauge to show near "empty"
the warning light will also go on.
Notice that when the tank is already full, the fuel is up to the ceiling of
the tank and the float does not have any room to go anywhere so it
stays submerged in fuel. It will not move until the fuel level drops...
You may have noticed how your gauge tends to stay on full for quite
a while after filling up. So I am pretty sure filling the hoses from
the filling cap down when you top-off would not change a thing...
That's what I saw. From my experience, I tend to over fill alot, and
slowly I noticed my previous Altima lose accuracy in detecting low
feul levels.
Your observation may be true, but the correlation between topping
off and diminishing fuel measuring accuracy totaly not existent...
What you probably see is the variable resistor in the sending unit
getting old and dirty, not conducting electric current like it used to
when it was brand new. That is all. I would not blame topping off.
Fair enough. I'll continue to top off with confidence then!
CD
|
--
Bill |
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jim
Guest
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| Posted:
Fri Nov 25, 2005 9:15 am Post subject:
Re: Cheating gas station? True tank capacity? |
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willshak wrote:
| Quote: | On 11/23/2005 10:44 PM US(ET), ??? took fingers to keyboard, and typed
the following:
Topping off is generally not a good idea environmentally. Much of the
extra fuel just evaporates.
Today's gas caps are not vented as they were in the past. That's why the
Check Engine light can come on when the caps are not tight. Even if they
were vented, are you saying that the gas in a few square inches of
surface area, like in the filler neck, is likely to evaporate more than
if the surface area of the gas was as wide and long as the gas tank?
That goes against what little I know of physics.
On Tue, 01 Nov 2005 20:49:19 -0500, Codifus <codifus@optonline.net
wrote:
Pszemol wrote:
"Codifus" <codifus@optonline.net> wrote in message
news:hZQ9f.4976$ex4.2044@fe08.lga...
Well, I replaced the feul pump in my sentra and attached to it I
found a mechanism which I beleive is the low feul warning
mechanism. It seems to work just like the the plunger in a toilet
bowl. This ball with air in it floats above the gas. That floater
is tied to a somewhat flimsy metal rod which attaches to some sort
of circuit. The circuit apparently measures the swing of the rod.
If you fill up with too much gas the "floater" may be pushed too
far, bending the flimsy rod a little, and thus fmaking the
mechanism lose its accuracy at detecting low feul levels.
What you saw is the fuel gauge sensor, sometimes called a "sender
unit".
The warning light is usually made as an addition to the fuel gauge:
when
the electric current flowing through the variable resistor in the
sending
unit and the gauge is large enough for the gauge to show near "empty"
the warning light will also go on.
Notice that when the tank is already full, the fuel is up to the
ceiling of
the tank and the float does not have any room to go anywhere so it
stays submerged in fuel. It will not move until the fuel level drops...
You may have noticed how your gauge tends to stay on full for quite
a while after filling up. So I am pretty sure filling the hoses from
the filling cap down when you top-off would not change a thing...
That's what I saw. From my experience, I tend to over fill alot,
and slowly I noticed my previous Altima lose accuracy in detecting
low feul levels.
Your observation may be true, but the correlation between topping
off and diminishing fuel measuring accuracy totaly not existent...
What you probably see is the variable resistor in the sending unit
getting old and dirty, not conducting electric current like it used to
when it was brand new. That is all. I would not blame topping off.
Fair enough. I'll continue to top off with confidence then!
CD
There is probably a scavenger system to reduce emissions which absorbs |
the fuel vapour from the top of the tank when under positive pressure,
where it is stored in a cannister of absorbent material (carbon?). It is
released under a partial vacuum situation. Perhaps when the filler
throat is full it upsets things?
Is it possible that when the |
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