I got my beautiful BRG cat about a month ago. Totally love the car, but I have not been able to get anywhere near the gas tank capacity with my fill ups.

At the last stop, my trip computer said the range was down to 20 miles. However, she only took 17.7 gallons!

Anybody ever had symptoms like this? Capacity is supposed to be 23 gallons, right? Is it possible that there is some kind of air bubble in the tank?

Thanks!

-Burt

 

From my copy of the X350 Technical Notes of mid-2003: -

- normally aspirated 85 litres (18.7 Imperial gallons - 22.4 US gallons)
- supercharged 84.5 litres (18.6 Imperial gallons - 22.3 US gallons)

I think you'll find there is some caution applied to the range calculation. If you just keep driving, a warning light will come on, (I think, but check the Driver Handbook). I doubt you have an air bubble.

 

To date the most I put in the XJR is around 78 litres, and that was with the range on zero.

There is quite a big reserve built in to the range calculation. It's normal.

My old X-Type once went 95kms (59mi) past the zero on the range indication & still had about 1L left in the tank.

Don't worry about it.

 

Admittedly mine is a diesel (not available in the US I understand) but it has an 85 litre tank.

A couple of months ago I had the 'low fuel' warning come up with a range figure of about 40 miles, and the fuel gauge reading about half-way down the red sector. Now as I had in the back of my mind Clarkson's experience on the 'Top Gear' Basel to Blackpool Economy Race I thought 'Nae prob' and drove the 14 miles home.

Next morning, with the range saying 26 miles I drove another 14 miles to my then usual filling station. Now, I fully expected it to use more fuel as it was starting from cold (ambient temp was ~50F/10C) but by the time I reached the filling station the range was down to one and the gauge right down at the bottom of the red sector ... and as I pulled up at the pump the range clicked down to zero.

Still unfazed I filled up ... and ... put 84.35 litres into it (I've double checked - that's what's printed on the receipt/check )

Now this is really odd because the diesel is supposed to have an automatic cut-off before the tank is completely empty; it runs 'rough', to simulate fuel starvation, for one mile and then stops completely in order to protect the fuel pump from having air run through it. In the Technical Guide for the 2.7 Tdvi it says that this cut-off occurs with about four litres remaining in the tank, thus the maximum possible fill for 2.7 Tdvi should be about 81 litres...so what happened ?

It seems to me that either
... the true tank (and filler pipe) capacity is at least four litres more than claimed, or
... the auto cut-off failed and I really was only a gnat's whisker away from running out, or
... that the filling station's pump was seriously (indeed illegally) out of spec.

Thoughts anyone ?

Diesel bretheren's experiences ?

 

Great feedback.

I wouldn't be surprised if that diesel pump was mis - calibrated. I remember a fill up years ago at a Chevron in Texas that rang up 2 gallons more than the car's capacity (confirmed by previous fillings).

In my XJR, the low fuel light had come on about 10 miles before I pulled in for gas. I think I will push my luck a bit more at the next filling to see if I can squeeze a few more gallons into the tank.

I am worried about it though because I have a 1990 ZR-1 that actually does have a 4 gallon air bubble. It's got a 20 gallon tank. However, when I ran out of gas one day (on my wife's birthday no less), it only took 16 gallons. I learned from the Corvette Forum guys that those older tanks have a vinyl lining which can delaminate and get an air bubble.

Anybody ever run out of gas in their x350? How much did it take?

Thanks again.

 

Well the accuracy of filling station pumps in the UK are periodically checked by the local Trading Standards office ('Weights & Measures' they used to be called) ... you can usually see a sticker on the pump saying when it was tested; +1% / -½% is the legal tolerance.

(But ... I don't go to that station any more ... just in case ...)

The acid test 'though is your question: Anyone run out ... whadidit take ?

 

Partick, I concur: great feedback and you like risks!
I was always wondering how reliable was the range indication given by the ODB, whether based on an actual measure with a sensor in the tank or on a calculation using integration of the engine consumption in real time. Anyway in your case it seems, assuming your cutoff failed, that the indication was very close to reality

 

I drove mine today till the red light came on it took 74.85 litres to fill it right to the top $113
Dam I miss the days when it was $30 to fill the tank LOL

 

Opinion at our old power engineers lunch (pub) club today (2.physicists, 2.chemists, only 1.engineer actually) was that most probably the tank is a bit more than 85 litres (so that people can't complain) ... in the same manner that speedos are a bit optimistic so you can't complain at the car maker if you get a speeding ticket.

I don't normally take risks like that, and I'm left wondering how much further it would have gone. It's the diesel artificial cut-off at 4 litres would seem to imply a real capacity of 88.5+ litres.

Yeh - that particular tankful cost £124 - ouch ! On the up side I only use the beast for longer distance journeys, and I didn't put any fuel in it in June, or August.

Diesel is now more expensive than gasoline here in the UK; has been for quite a few years

 

Its similar here in Australia diesel is more expensive but the price does not fluctuate daily like fuel
We also have 3 types of fuel 92 unleaded 95 premium and 98 premium
Normal unleaded can be cheaper than diesel sometimes 10 to 15 cents but it can also be the same or dearer

The 95 premium is 7 cents dearer than 92 unleaded and the 98 is 10 cents dearer no logic there
I filled with 95 octane yesterday they didn't have 98
I like to use the 98 either BP ultimate or shell Vpower

My wife's Jeep has a Mercedes OM642 diesel engine it gets exceptional fuel economy for such a big vehicle has a tune 3 inch exhaust egr switched of and KN filter I also run TC-W3 in the fuel mix at 3.2 ML per litre

My XJ8 4.2 is pretty economical for a V8 my previous XJR6 best it could do was 600 to a tank on the open road and that's with a lot of modifications as well before the mods it would only do 450k to 500k per tank the XJ8 sees 750 to 800 regularly I also run TC-W3 in the XJ8 at 1.9 ml per litre
My next XJ is going to be a diesel twin turbo 3.0 would be nice fair bit of scope there to tune and extract more power from

The Jeep diesel with the mods I have went from 165KW to 210 KW but the torque went from 570 nm to 710 nm love that

The torque boost makes it very easy to drive as the torque comes in much lower than the standard tune

The tuner also got rid of the typical diesel delayed throttle response floor it now with traction control off and it will spin all 4 wheels up my driveway fuel economy lifted as well when it was totally standard the gauge would read 11 to 13 K per litre it now does 10 and on a trip I see under 9 the TC-W3 improved economy quite a bit also quietened down the diesel engine rattle

 

I've done it again !

I went on a church bell ringing trip in the Cotswolds yesterday and it started to look very low as I approached home. As I run it on Shell V-Power/ BP Ultimate/ Esso Supreme diesel rather than 'diesel ordinaire' I decided to make a run for usual filling station.

The range went to zero as I passed where I live, and I 'chickened out' about three miles later and put 10 ltr of Merco 'plonk' in it; then went on another five miles to my usual Shell station ... where I put 73.75 ltrs (£106 )in it when the range would have been -8 miles (if the range could go negative).

That's a total of 83.75 litres at 8 miles beyond zero-range; it was 84.35 at zero range last time.

I do suspect that the tank is a few litres more than the quoted 85.

Has anyone run a gasoline one right out and know what it took to refill ?

 

Patrick
Try A ratio of 3.2 ML per litre of TC-W3 outboard oil in the tank with the diesel and see the difference in economy

It would also be wise to get rid of the egr valve as well have a look at a flash tune which will disable the EGR

I have a flash tune in my diesel Jeep om642 3.0 Mercedes V6 engine the TC-W3 made the engine super quiet cant even hear its a diesel and much better economy search the net if you don't believe me there are hundred's o0f pages on it
I use it in all my cars and bikes for 4 years now

 

I want to add two thoughts to this discussion. I might be wrong about these ideas, but that is the way my experience has led me to see it.

1. Regarding the "miles to empty" issue: I think the computer is telling you a distance based on the average mileage, not the distance you could get if you drove in a way to achieve maximum possible mpg.

2. Regarding the existence of an "air bubble" in the gas tank that limits the amount you can add to something less than the actual capacity: I suspect that the variable is not in the gas tank. Gasoline filler nozzles here in the USA have a back pressure actuated shut off feature. I suspect that they work that way most everywhere since that is what avoids a neglected nozzle from pouring gas all over the ground if you are in the bathroom or whatever.

I travel all over the Western USA. I frequently encounter the phenomena of not being able to completely fill the tank. Then on my next fillup no problem at all. Same gas tank, so the variable factor has to be the pump/hose/nozzle I am using at the time.

Just my .02

Tom

 

thxalot

if your 2004XJR is like mine, the fuel gauge may be off, messing up the computer calculations. My fuel sensors have been replace 3 times in 76K miles. One time by the dealer, second by and indie and third time by me! Note that there are 2 sending units. One on each side and can be replaced by removing the rear seat. Fuel tank access ports are directly below.
RyeJag