>> Can someone tell me what might be the gallons that register from the
>> 1/8 mark to 1/4 mark meaning how many gallons between these two marks.
[quoted text clipped - 5 lines]
>check the gallons readout on the pump. The tank isn't symmetrical so the
>number of gallons between marks will be different at different fuel levels.
Problem with this is that Chrysler filters the gauge readings (all of
them!) through the PCM. This creates two problems:
1. The reading takes a while to stablize (done to prevent the needle
from moving as gas sloshes around as you are driving) and,
2. Once you open the cap with the key on, the PCM detects an evap
error and can set a code (OK, the code is trivial, and will eventually
clear on its own.)
The first problem above is the more serious one. Easier to do is to do
this in three steps..
1. Get to 3/4 tank, and fill it to the recommended level. Get the
owner's manual and check how much the tank holds (usable volume).
Subtract what you put in from the full tank amount, and that's what
remains at 3/4 tank.
2. Get to 1/2 tank, and fill it to the recommended level. Subtract
what you put in from the full tank amount, and that's what remains at
1/2 tank.
3. Get to 1/4 tank, and fill it to the recommended level. Subtract
what you put in from the full tank amount, and that's what remains at
1/4 tank.
4. Get to 1/8 tank, and fill it to the recommended level. Subtract
what you put in from the full tank amount, and that's what remains at
1/8 tank.
Takes four trips to the gas station, and a bit of simple math, but it
will be more accurate than tryign to wait for the gauge to stablize as
you are filling.
Nosey - 02 Feb 2008 18:28 GMT
> Problem with this is that Chrysler filters the gauge readings (all of
> them!) through the PCM. This creates two problems:
>
> 1. The reading takes a while to stablize (done to prevent the needle
> from moving as gas sloshes around as you are driving) and,
That's why I said slowly. I re-fuel my '99 by watching the fuel gauge every
time. I re-fuel from my garage and my nozzle doesn't have an automatic
shut-off. When it gets close to the full mark I slow the pump down. When the
needle is just above the full mark I shut it off. I've never over-filled it.
> 2. Once you open the cap with the key on, the PCM detects an evap
> error and can set a code (OK, the code is trivial, and will eventually
> clear on its own.)
I don't think it'll set any codes if you take the cap off with the key on
(engine off). The PCM controls the evap purge solenoid based on engine
operating conditions. I think the PCM knows when the engine isn't running,
but I could be wrong.

Signature
Ken
nunya - 12 Feb 2008 13:38 GMT
<snip>
> That's why I said slowly. I re-fuel my '99 by watching the fuel gauge
> every time. I re-fuel from my garage and my nozzle doesn't have an
> automatic shut-off. When it gets close to the full mark I slow the pump
> down. When the needle is just above the full mark I shut it off. I've
> never over-filled it.
<snip>
same routine here. i buy all my fuel in bulk for the convienence of not
having to stop at places where i am not sure of their storage tanks. i did
just buy a nozzle with an automatic shut off so that i don't have to worry
about employees accidentally pouring my fuel out on the ground.
not to mention that i have discovered that about 20% of the local bp/amico
stations are not actually putting bp branded gas in their tanks. several of
the pakistaniranian owners are actually selling the off brand and blended
stuff from the hub to make a couple of extra cents.
michael
Nosey - 13 Feb 2008 04:40 GMT
> not to mention that i have discovered that about 20% of the local
> bp/amico stations are not actually putting bp branded gas in their
> tanks. several of the pakistaniranian owners are actually selling
> the off brand and blended stuff from the hub to make a couple of
> extra cents.
I don't worry too much about that. I make my own fuel.

Signature
Ken
nunya - 12 Feb 2008 13:32 GMT
<snip>
> Problem with this is that Chrysler filters the gauge readings (all of
> them!) through the PCM. This creates two problems:
[quoted text clipped - 29 lines]
> will be more accurate than tryign to wait for the gauge to stablize as
> you are filling.
i think i need a nap after all that addiplicating.
i have ~280k on my daily driver and have never even thought about this
conundrum. when my truck get to a quarter tank i fill it back up. if you
drive around with much less than a quarter tank in the 100 degree georgia
hot sun for long you get to put in a new fuel pump more often than you would
like.
michael