Fuel gauge not going up after filling up

pletevl · 28th July 2022, 08:03

Hi all.
I was low on fuel so filled up the tank, to the brim, but the gauge hasn't gone up. Its still just above the red and the light is on.
2005 cdti automatic.
Any ideas?

Pete.

The Rovering Member · 28th July 2022, 14:24

There are two sender units in the tank, on my car the passenger side sender is up the creek. I've been using the trip meter for filling up for a couple of years now.

Other causes are available.

SD1too · 28th July 2022, 16:17

Another member with a diesel looked into this in great detail. He found that the rheostat on one of the floats was damaged over a small area. If you're handy with a multimeter you can check for the correct resistances.

Simon

dave lincs · 28th July 2022, 16:42

Do you have an IPK/Trip computer if so check distance range if that indicates high range do a battery reset

pletevl · 29th July 2022, 06:44

Just checked, it says range 75 kms.
Is this a known fault? Are the parts available? If not then I'll try to live with it.

Gate Keeper · 29th July 2022, 07:31

Quote:

Originally Posted by The Rovering Member

There are two sender units in the tank, on my car the passenger side sender is up the creek. I've been using the trip meter for filling up for a couple of years now.

Other causes are available.

We use the same method of trip meter and Sat Nav for speed as the fuel gauge on the loaned Audi and the speedo is working intermittently. To have the Audi repaired would cost more than it’s worth, so we get by using the method you described. After filling up, I record the litres put in and I set the trip meter to zero and take it from there.

The Rovering Member · 29th July 2022, 22:39

I just fill up at around 350 as l know the car does 400 or so to the tank.

pletevl · 7th August 2022, 13:45

Can the hot weather affect the fuel floats in the tank?
Now the weather is cooler, everything has started working correctly ��

gnu · 8th August 2022, 17:52

The problem can be intermittent. I’ve had my ZT around 5 years now and had the back seat out to check the fuel pump and filter assemblies twice now, due to an untruthful gauge. After cleaning the rheostat tracks and wired connections and refitting the parts the gauge worked again, both times.

I still keep a manual record though, as a backup. I also avoid ‘brimming’ as that is what seemed to bring on the problem both times. I have to say, watching the gauge closely can gives some fairly large variations between initial start up and a bit later in the journey (as the ecu settles on what to display).

There’s some good historic threads, on the problem, on this site if you do a search.

JosephJ · 19th August 2022, 08:52

If needed, you can read the resistance from the plug under the back seat. If you look at the plug from above (looking at it from the rear driver's door) it'll be the first pins on the left (1 and 4 I think) for one float and the two pins on the right (3 and 6) for the other float. They are connected by a little jump wire in the loom which the IPK reads. It's definitely less messy than removing the floats!

Sent from my Pixel 6 Pro using Tapatalk

28th July 2022, 08:03	#1
pletevl Posted a thing or two rover 75 cdti(rhd), MG ZR(lhd), MG TF(lhd), MG TF(rhd), mini mpi (lhd), Renault megane III (awful) Join Date: Mar 2014 Location: East of France Posts: 1,278 Thanks: 124 Thanked 114 Times in 93 Posts	Fuel gauge not going up after filling up Hi all. I was low on fuel so filled up the tank, to the brim, but the gauge hasn't gone up. Its still just above the red and the light is on. 2005 cdti automatic. Any ideas? Pete.

28th July 2022, 14:24	#2
The Rovering Member I really should get out more....... Rover 75 saloon Join Date: Feb 2014 Location: London Posts: 2,953 Thanks: 263 Thanked 538 Times in 431 Posts	There are two sender units in the tank, on my car the passenger side sender is up the creek. I've been using the trip meter for filling up for a couple of years now. Other causes are available. __________________ Reducing the size of my Rover fleet by adding a 75 to it.

28th July 2022, 16:17	#3
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,345 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	Another member with a diesel looked into this in great detail. He found that the rheostat on one of the floats was damaged over a small area. If you're handy with a multimeter you can check for the correct resistances. Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

29th July 2022, 22:39	#7
The Rovering Member I really should get out more....... Rover 75 saloon Join Date: Feb 2014 Location: London Posts: 2,953 Thanks: 263 Thanked 538 Times in 431 Posts	I just fill up at around 350 as l know the car does 400 or so to the tank. __________________ Reducing the size of my Rover fleet by adding a 75 to it.

8th August 2022, 17:52	#9
gnu Gets stuck in MG ZT Join Date: Apr 2018 Location: Bristol Posts: 695 Thanks: 332 Thanked 164 Times in 133 Posts	The problem can be intermittent. I’ve had my ZT around 5 years now and had the back seat out to check the fuel pump and filter assemblies twice now, due to an untruthful gauge. After cleaning the rheostat tracks and wired connections and refitting the parts the gauge worked again, both times. I still keep a manual record though, as a backup. I also avoid ‘brimming’ as that is what seemed to bring on the problem both times. I have to say, watching the gauge closely can gives some fairly large variations between initial start up and a bit later in the journey (as the ecu settles on what to display). There’s some good historic threads, on the problem, on this site if you do a search. __________________ gnu

28th July 2022, 16:42	#4
dave lincs Posted a thing or two Rover 75 Saloon Join Date: Mar 2014 Location: Louth Posts: 1,409 Thanks: 380 Thanked 986 Times in 476 Posts	Do you have an IPK/Trip computer if so check distance range if that indicates high range do a battery reset

29th July 2022, 06:44	#5
pletevl Posted a thing or two rover 75 cdti(rhd), MG ZR(lhd), MG TF(lhd), MG TF(rhd), mini mpi (lhd), Renault megane III (awful) Join Date: Mar 2014 Location: East of France Posts: 1,278 Thanks: 124 Thanked 114 Times in 93 Posts	Just checked, it says range 75 kms. Is this a known fault? Are the parts available? If not then I'll try to live with it.

7th August 2022, 13:45	#8
pletevl Posted a thing or two rover 75 cdti(rhd), MG ZR(lhd), MG TF(lhd), MG TF(rhd), mini mpi (lhd), Renault megane III (awful) Join Date: Mar 2014 Location: East of France Posts: 1,278 Thanks: 124 Thanked 114 Times in 93 Posts	Can the hot weather affect the fuel floats in the tank? Now the weather is cooler, everything has started working correctly ��

19th August 2022, 08:52	#10
JosephJ Avid contributor Rover 75 Saloon Join Date: Jul 2021 Location: Basingstoke Posts: 104 Thanks: 0 Thanked 3 Times in 3 Posts	If needed, you can read the resistance from the plug under the back seat. If you look at the plug from above (looking at it from the rear driver's door) it'll be the first pins on the left (1 and 4 I think) for one float and the two pins on the right (3 and 6) for the other float. They are connected by a little jump wire in the loom which the IPK reads. It's definitely less messy than removing the floats! Sent from my Pixel 6 Pro using Tapatalk