Noticed the last two times I got gas (fill up) that the tank was not showing full as I pulled away. First time didn’t give it much notice. Second time I wondered if there wasn’t something off with the pump as both fill ups were at the same station and the same pump. Now I’m paying attention.

In my previous FType, I had the issue where the pump would cut off after just a few gallons and you would have to rotate the nozzle to get it to accept. Was a problem with the fuel filler neck I believe and somewhere floating around is a TSB for it. From that, I got pretty good at estimating how many gallons I would need at each fill up before I got it fixed. Current FType does not have this same issue.

For this last fill up I was at a different station, in a different town. Expected to need approx 13 gallons based on gauge level. Pump clicked off at just over 10. Nudged the car a bit and fed in a little fuel to see if it would take more. Fuel was visible in the filler neck and level was not going down as I bumped the car again. Fuel that ran out when bumped drained down the overflow tube (there was minimal amount). Led me to believe it was truly full. I told myself I hadn’t yet had coffee and must have just looked at the gauge wrong. Nope. Start up and I have a gauge showing over 3/4 tank but not even close to full.

Did a search here and can’t seem to find similar reports for other FTypes. There was an instance reported in an older (2012) XF but that was also a single report. A few more in the XJS threads. All reported Fuel Sender Sensor.

My first thought was a breather tube came loose (?) but I only have rudimentary knowledge of fuel systems, so it’s a guess.

This is on 2017 V6S, just over 51k on the odometer. Approx. 10k of those miles are mine. I don’t run the tank empty (it just goes against everything in my soul), top tier fuel only. No CEL.

She’s under warranty and going to dealer on Friday after I take a few days to run the tank down (darn the luck!). But mostly curious if anyone else has experienced anything similar?

 

My fuel gauge would never get below ‘48 miles to empty’, just above the red mark. Even showed that when I ran out of gas on I-90 in MN. It now rarely goes below 1/2, I use the trip odometer. Haven’t gotten around to having it fixed, but it was pretty clearly defective from the factory.

 

Did you post about that here? Seems I remember someone had an adventure trying to get fuel a few years back. That may not have been you though.

Regardless, thanks for the comment. I’ll update once I have more info from shop.

 

https://www.jaguarforums.com/forum/f...-empty-235265/

The fuel gauge worked OK for 7 years or so, though never getting below about an 1/8th of a tank. When I took it out of winter storage a couple of years ago, the gauge didn’t move at all for the first tank. After that, it only goes down to about 1/2.

The dealer indicated there’s an access port somewhere for accessing the tank, so replacing the sender isn’t a huge job. They suggested replacing the pump while there. As they pissed me off on another job (they’ve always been good if expensive), I didn’t follow up.

 

You might try running some Marvel Mystery Oil (in the recommended dosage for fuel) through the gas tank a couple of times. I used to own a Nissan 370Z and wonky fuel gauges were a known issue. I ran nothing but top tier fuel through it but a few times a year the gauge would fail to read full. MMO cured it for several tanks and it would reoccur again. The MMO acts as a solvent and your car's fuel level sensor or float may be a bit sticky. It's certainly worth about $7-$8 to try.

 

I have had gas gauge problems on a different car and the suggestion was to try an additive that had a high PEA content?
Here is a thread discussing it. I tried one of those high PEA products and noticed no change but it was a suggestion?
PEA Additive for Fuel Gauge?
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Thanks, I do an annual BG44K treatment.

 

Funny I do to!
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