Ugh! I can't imagine how bad it would be to run the KJ dry. I tried changing fuel filter just once. Pain in the booty it was. Had to shoot compressed air into the fuel tank to prime the darn filter head! I'd been operating the primer rod on the fuel filter head for minutes on a two-man shift (because your hand gets raped by the metal hole which the primer rod goes into) and nothing happened.

Just never run out of fuel is what I intend to do!

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L.O.S.T forever!
Silver 2002 Skoda Fabia TDI, 235,000km
Former car: Jeep KJ 2003 CRD

DIESEL - saving millions of liters of petrol every day!

Mine seems to be remarkably consistent between 1/4 and Full at least - put in 5 gallons, and it goes up 5 graduations on the gauge. And there's 4 gallons at least above the full mark on the gauge. I've gotten to where I can call it within +/- 1 gallon what it will take to fill up just by looking at the fuel gauge. Normal fillup at 1/2 tank, it'll take 12 gallons - 8 gallons from 1/2 to Full, and 4 gallons above full.

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Mitchell Oates
'87 MB 300D Diamond Blue Metallic
'87 MB 300D - R.I.P. 12/08
'05 Sport CRD Stone White
Provent CCV Filter/AT2525 Muffler
Stanadyne 30 u/Cat 2 u Fuel Filters
Fumoto Drain/Fleetguard LF3487 Oil filter
V6 Airbox/Amsoil EAA Air Filter
Suncoast TC/Shift Kit/Aux Cooler
Kennedy Lift Pump/Return Fuel Cooler

Uffe.

Put a lift pump in the tank and it's automatic

Joe

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

Yeah I know what you mean. I want to mod that jeep, I really do. I'm currently thinking of fitting and EGT gauge and maybe trans temp gauge. Not sure how to do that easily. I think it will be a PITA to do. Then there's the money issue, I mean, it's just after christmas

Then there's the lift pump, the suncoast TC, lifting, tyres, rims ... the list seems endless

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L.O.S.T forever!
Silver 2002 Skoda Fabia TDI, 235,000km
Former car: Jeep KJ 2003 CRD

DIESEL - saving millions of liters of petrol every day!

If for airplanes they can have the following guidelines (see below), I'm sure the Caddy engineers could come up with something similar - I am just stating that the public does not want this - and to my knowledge the fedral regulations are very loose if not existent.

REGULATIONS FOR AIRPLANE FUEL GAUGES - almost linear I would say:
TSO-C55 specifies a tolerance of 3% of full scale. This applies to the whole system, end-to-end, including the sensor in the tank as well as the gauge. (Note that the sensor is sometimes called a transducer, but more often called a fuel sender or fuel quantity sender.)
# Similarly, expired standard MIL-G-26988C (reference 3) specified the following:

Class I: ±4 percent of indication, ±2 percent of full scale
Class II: ±2 percent of indication, ±0.75 percent of full scale
Class III: ±1 percent of indication, ±0.5 percent of full scale.

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It's got a CRD, sweet! (KJ Newbie since 2002!)
- KJ 14 mpg replaced with WK 28 mpg
- OEM hitch and OEM tow harness added
- Reese Pilot brake controller

Hey, if they could build a Jeep with the budget of a jet I'm sure it could be done. I wasn't saying it was technically impossible, just difficult and probably more trouble than its worth.

That said, if such a Caddy exists I want to know what year and model. If its not an urban legend, that should be fairly easy to determine, after all some of them would have had to have been sold for them to have been 'flooded with complaint calls'.

All that aside, I agree that I'd like to see a more accurate gague. Its not any less accurate than my previous vehicle was though(Chevy S-10).

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2006 Jeep Liberty Sport CRD

Can someone with an SGII please find out if they can read the fuel information and find out if it's the sender or the gauge which is non-linear. I believe it would not be difficult to make a linear gauge but the problem lies more in the sender unit.

How to sense a proper amount of fuel in the tank depends on how the measurement is taken. If you just measure the level you have to account for the shape of the fuel tank. It would not at all be impossible to make a simple translation from level to amount just be filling it one liter at a time and using the senders feedback and note down the amount you put in and the reading of the sender. Then make some interpolation table implementation in the car computer and route the sender signal through the car computer and the adjusted value from the car computer into the gauge.

Problem is more with the senders range than with the translation of the signal IMO.

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L.O.S.T forever!
Silver 2002 Skoda Fabia TDI, 235,000km
Former car: Jeep KJ 2003 CRD

DIESEL - saving millions of liters of petrol every day!

I have complained about the fuel sender from day one with the CRD. The dealer actually replaced it once with no help. I also accused Jeep of using a float from a Gasser or ????that rides higher in the tank due to the difference in fuel density or tank volume differance.

What is doubly annoying is that I know Jeep can make an accurate gage/sender system as my GC gage has 20 graduations and each one represents 1 gallon....and it works from F to E.

It would be interesting if someone that pulls the unit for boost pump install would masure the tank inside dimensions and then the swing of the arm against the sender output.

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2006 Libery Sport CRD, Lt Kakhi, nicely equipped
*****GDE Hot Tune at 38,879 miles
*****Stock TC.....for the time being!!

Actually, it's not hard at all. For older analog cars, it just requires a little signal preprocessing with an op-amp network. For newer vehicles like the CRD, it can be done virtually for free in the module which drives the information onto the local bus.

- Chris

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Used to own:
2006 CRD Sport
Suncoast TC, Transgo shift kit, Inmotion, ORM, EHM, Magnaflow SS exhaust, Fumoto valve, EVIC added, Hensley TruControl brake controller, Pirelli Scorpion ATR LR-D in spring/summer/fall, FIA winter front and Blizzaks in winter

So how do you account for the difference in filling up of the vehicle, ie: how some people top off, some do not, etc etc? How about on hills and other gradients? What about when warm or cold? At other altitudes where the fuel will expand or contract naturally due to the lower atmospheric pressure?

It seems to me it would need a ton of sensors to determine its environment and the usage pattern of the driver in order to make a perfect fuel gauge, or am I missing something obvious here?

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2006 Jeep Liberty Sport CRD

I think what the previous poster meant is that the exact same amount of fuel was represented by each quadrant of the fuel gauge, and that its relationship to quantity was exactly linear. I'm sure there would be arbitrary travel above the range depending on overfilling, and some travel below the gauge to account for safety margins. However, I'm sure they did much better than my CRD which reads nearly 100 miles by the time the needle comes down to "F".

- Chris

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Used to own:
2006 CRD Sport
Suncoast TC, Transgo shift kit, Inmotion, ORM, EHM, Magnaflow SS exhaust, Fumoto valve, EVIC added, Hensley TruControl brake controller, Pirelli Scorpion ATR LR-D in spring/summer/fall, FIA winter front and Blizzaks in winter