Fuel Tank Parameters

[hquick]

I just realised after installing the 0411 in my 98 Burb that the fuel tank was set at 116L. Mine is 159L so I changed it in the primary tank (F0504) and Fuel Tank (F0502)Size. Both now set at 159L.
What should (F0506) upper sender limit be set at?
I noticed in some other tunes it's set at 150L (actual tank being 116L) where there is a Max of 200.
In my parameters it allows for a max of 255L so I set it at 200. Is this correct?

[350SS]

I just realised after installing the 0411 in my 98 Burb that the fuel tank was set at 116L. Mine is 159L so I changed it in the primary tank (F0504) and Fuel Tank (F0502)Size. Both now set at 159L.
What should (F0506) upper sender limit be set at?
I noticed in some other tunes it's set at 150L (actual tank being 116L) where there is a Max of 200.
In my parameters it allows for a max of 255L so I set it at 200. Is this correct?
Hey Howard,

You would think you and I are working on the same exact truck, just in opposite hemispheres :muahaha:

I was just working on the fuel gauge setup for my truck as well, I'll be speaking in gallons though. So initially the tune was set for the following values under "fuel system parameters"

{F0502} Fuel Tank Size 30.643952 Gallons
{F0504} Primary Fuel Tank Size 30.643952 Gallons
{F0506} Fuel Sender Upper Limit 150.000000 A/D Converter Value

I changed my tank volume to 25 gallons (it's either 25 or 26 in reality, have to check on that one)

Changed to:
{F0502} Fuel Tank Size 25.001403 Gallons
{F0504} Primary Fuel Tank Size 25.001403 Gallons
{F0506} Fuel Sender Upper Limit 150.000000 A/D Converter Value

I left F0506 the same as you can see.
I left the "Fuel Gauge Calibration" table the same.

I attached an excel spreadsheet of the values that I put in the "Convert Sender to Volume" table. I basically took the original table up to the last zero in the table (labeled MIN), and then deleted all the values up to the first maximum value in the table (labeled MAX). Then I changed all the maximum values to reflect the volume of my tank (25 gallons). Finally I scaled the cells inbetween the last "zero" and first "25" so that it has a linear scale increase. This is probably hard to understand with me explaining it in type but hopefully will be clear when you look at the attached excel file. I think this worked out okay, and my gauge seems to be functioning properly now.

Max :cheers:

[hquick]

Ha! Ha!
Are you stalking me or am I stalking you? :Eyecrazy:

Thanks for the table...that makes sense. I'll apply it to mine.

Howard

[hquick]

Thanks Max,
I just applied your method to my own cal.
The only thing I'm not sure of is what the upper limit should be set at?
The original tune with the 116L tank is set at 150.
Mine has the 159L tank and the upper limit is a possible 255L. I have set it at 200 for the moment but I don't understand it completely.
Maybe Ross or Paul can chime in on this one?

[hquick]

Hey Max,
send me an email hquick@bigpond.com
I'll send you some interesting info I just found looking at another tune.
It's kinda back to front from ours???
I'll send you the tune!

[350SS]

email sent ;)

[350SS]

The only thing I'm not sure of is what the upper limit should be set at?
The original tune with the 116L tank is set at 150.
Mine has the 159L tank and the upper limit is a possible 255L. I have set it at 200 for the moment but I don't understand it completely.
Maybe Ross or Paul can chime in on this one?

I would leave it set at 150...I'm pretty sure that it corresponds to a number that reflects the reading the fuel sender puts out which corresponds to the maximum volume of the the tank, rather than an actual volume number.

In my tune I changed the tank size numbers, but left the fuel sender upper limit value the same:


Original tune:
{F0502} Fuel Tank Size 30.643952 Gallons
{F0504} Primary Fuel Tank Size 30.643952 Gallons
{F0506} Fuel Sender Upper Limit 150.000000 A/D Converter Value

I changed my tank volume to 25 gallons (it's either 25 or 26 in reality, have to check on that one)

Changed to:
{F0502} Fuel Tank Size 25.001403 Gallons
{F0504} Primary Fuel Tank Size 25.001403 Gallons
{F0506} Fuel Sender Upper Limit 150.000000 A/D Converter Value

I left F0506 the same as you can see.


Hope I'm explaining that okay :)

[350SS]

Hey Max,
send me an email hquick@bigpond.com
I'll send you some interesting info I just found looking at another tune.
It's kinda back to front from ours???
I'll send you the tune!
That's interesting...the Fuel Gauge Calibration table has and inverted slope compared to the one our file has. Keep in mind that, from the description, that table is the one that the pcm uses to modulate the vehicles fuel gauge. So depending on the vehicles gauge, it may require a pwm signal that is the inverse of what our gauges require. I'm not 100% sure on that, it's just a guess. I'd be willing to bet that if you used those values, your fuel gauge would read empty when full and full when empty. Wanna be the guinea pig? j/k I don't want anything to get screwed up on your truck.

[Garry]

Speaking of fuel tanks - the F-Body fuel tank is pretty bad as far as the stock calibration goes. The gauge reads full pretty long, with half meaning about 2/3 of the fuel being gone, and quarter full being about 1/8th left ... has anybody here tried to set up a new calibration table that corrects this gauge behavior?

[hquick]

Mine's still not quite right Max.
I filled up today 'cause I'd driven 300k's or so and the needle was barely below full.
I filled it to the brim (only got 55L in it so it already had 104L or so). The Fuel tank level PID says 100% where as it was saying 80.8% before filling it.
Now, I need to work out how to scale the sender. The needle is as far to the right as it can go...past the circle. I want to try and make it so that 'Full' is on the white line and 'Empty' is on the red line.

[hquick]

Sorry...double post!

[Lextech]

I haven't noticed this on my truck. I don't run it from full to empty though. I like to keep it just about full to try to help with traction--I know that adds weight and is counter productive. When I get the truck out in a few weeks, I'll have to pay attention to the fuel gauge.

[hquick]

Does anyone have one?