The trip computer fuel used is way off, the trip mileage is accurate as I checked it with known distance as I drive it everyday to the office. This also causes the computer to display incorrect L/100 or MPG, I really do not think that a 96 XJR gets 35 US mpg in the city or 6.7 L /100km...lol. The joy to drive has 169500 kilometers on the odometer. Chatting with a couple of very gifted technicians last night an idea was perhaps an injector is dumping vs spraying but no smell of excess fuel in the exhaust. This last fill the computer showed 28 liters used and the pump was 55 liters to fill. The car is going back in next week to get the other 4 coils replaced and install XJEngineer's bracket...looking forward to enhanced performance...lol.
Any one have this challenge or perhaps some suggestions to pursue?
This forum and all the members have contributed immensely to helping technicians and myself to being proactive in restoring this Bad Cat to it's improved former self, I have been finding myself taking the long way home after work...lol

 

Someone will have a better answer.

I'm not sure how they all link together, but I would suspect a sticky tank sender unit, allowing false information to be sent to the computer.

My somewhat older 92 has this problem and many others have reported the same.

I gave up on the fuel gauge years ago, and now just keep an eye on distance travelled since a fill.

For your MPG, calculate it the old fashioned way.

 

Thanks Richard,

The fuel gauge is functioning well and I have been tracking fuel and miles/kilometers in my journal "the care and feeding of my cat"....lol...just did not have it on hand to manually calculate the old fashion way.

Regards
B3